🕷️ Crawler Inspector

URL Lookup

Direct Parameter Lookup

Raw Queries and Responses

1. Shard Calculation

Query:

Response:

Calculated Shard: 164 (from laksa184)

2. Crawled Status Check

Query:

curl -X POST \
  'http://laksa164.int.ahrefs:8124/' \
  -H 'Content-Type: text/plain' \
  -H 'X-ClickHouse-Database: crawler3' \
  -H 'Authorization: Basic YXBpOg==' \
  -d 'SELECT getAhrefsURLFromUnparsed(src_unparsed) AS found_url, ifNull(toUnixTimestamp(download_stamp), 0) AS crawl_time, ifNull(toUnixTimestamp(props_url_first_seen), 0) AS first_indexed_time, download_http_code AS http_code, src_unparsed AS src_unparsed, src_root_hash AS src_root_hash, history_drop_reason AS history_drop_reason, meta_title AS meta_title, meta_descriptions AS meta_descriptions, attrs_boilerpipe_text AS attrs_boilerpipe_text, attrs_markdown AS attrs_markdown, attrs_readable_markdown AS attrs_readable_markdown, meta_canonical AS meta_canonical FROM crawler3.page_info_local FINAL PREWHERE (src_root_hash, src_unparsed) IN ((getAhrefsRootHashFromUnparsed(getAhrefsUnparsedNoserviceFromURL(\'https://www.khanacademy.org/science/ms-physics\')), getAhrefsUnparsedNoserviceFromURL(\'https://www.khanacademy.org/science/ms-physics\'))) FORMAT JSONEachRow'

Response:

{"found_url":"https:\/\/www.khanacademy.org\/science\/ms-physics","crawl_time":1775827258,"first_indexed_time":1648751544,"http_code":200,"src_unparsed":"org,khanacademy!www,\/science\/ms-physics s443","src_root_hash":"3750796715567959364","history_drop_reason":null,"meta_title":"Middle school physics | Science | Khan Academy","meta_descriptions":["Learn physics using videos, articles, and NGSS-aligned practice exercises. Explore the fundamentals of motion and forces, non-contact interactions, energy, and waves."],"attrs_boilerpipe_text":"If you're seeing this message, it means we're having trouble loading external resources on our website.\nIf you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.\nSelect a category to view its courses\nLog in\nSign up\nSearch for courses, skills, and videos\nWelcome to Khan Academy!\nSo we can give you the right tools, let us know if you're a...\nMiddle school physics\n6 units · 22 skills\nUnit 1\nMotion and forces\nUnit 2\nNon-contact interactions\nUnit 3\nEnergy\nUnit 4\nWaves\nUnit 5\nExplore physics through simulations\nUnit 6\nTeacher resources\nCourse challenge\nTest your knowledge of the skills in this course.\nStart Course challenge\nScience\n2,100 possible mastery points\nMastered\nProficient\nFamiliar\nAttempted\nNot started\nQuiz\nUnit test\nUnit 1\nUnit 1: Motion and forces\nUnderstand: motion\nApply: motion\nUnderstand: forces and Newton's third law\nApply: forces and Newton's third law\nMotion and forces: Quiz 1\nUnderstand: connecting motion and forces\nApply: connecting motion and forces\nMotion and forces: Quiz 2\nMotion and forces: Unit test\nUnit 2\nUnit 2: Non-contact interactions\nUnderstand: gravitational force\nApply: gravitational force\nNon-contact interactions: Quiz 1\nUnderstand: electric and magnetic forces\nApply: electric and magnetic forces\nNon-contact interactions: Quiz 2\nNon-contact interactions: Unit test\nUnit 3\nUnit 3: Energy\nUnderstand: kinetic energy\nApply: kinetic energy\nUnderstand: potential energy\nApply: potential energy\nEnergy: Quiz 1\nUnderstand: conservation of energy\nApply: conservation of energy\nEnergy: Quiz 2\nEnergy: Unit test\nUnit 4\nUnit 4: Waves\nUnderstand: wave properties\nApply: wave properties\nUnderstand: sound waves\nWaves: Quiz 1\nUnderstand: electromagnetic waves\nApply: electromagnetic waves\nWaves: Quiz 2\nWaves: Unit test\nUnit 5\nUnit 5: Explore physics through simulations\nThis unit's exercises do not count toward course mastery.\nUnit 6\nUnit 6: Teacher resources\nThis unit does not include exercises.\nCourse challenge\nTest your knowledge of the skills in this course.\nStart Course challenge\nWelcome to middle school physics!\nWatch an introduction video\n2 minutes 25 seconds\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves.\nThis course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our\nhigh school physics\ncourse.\nGive us feedback on this course\nTeaching this course? Check out our\nteacher resources\n!\nLearn more\nWelcome to middle school physics!\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves.\nThis course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our\nhigh school physics\ncourse.\nGive us feedback on this course\nTeaching this course? Check out our\nteacher resources\n!\nLearn more\nWatch an introduction video\n2 minutes 25 seconds\nUnit 1: Motion and forces\nUnit mastery: 0%\nMotion\nIntroduction to middle school physics\nSpeed and velocity\nAcceleration\nReference frames\nDescribing motion\nUnderstand: motion\nApply: motion\nForces\nForces\nNewton's third law\nForces and Newton's third law\nUnderstand: forces and Newton's third law\nApply: forces and Newton's third law\nConnecting motion and forces\nNewton's first law\nNewton's second law\nConnecting motion and forces\nUnderstand: connecting motion and forces\nApply: connecting motion and forces\nUnit 2: Non-contact interactions\nUnit mastery: 0%\nGravitational force\nGravitational force\nGravitational force\nUnderstand: gravitational force\nApply: gravitational force\nActivity: How can a skydiver fall safely?\nActivity: How can a skydiver fall safely?\nElectric and magnetic forces\nElectric force\nMagnetic force\nElectric and magnetic forces\nUnderstand: electric and magnetic forces\nApply: electric and magnetic forces\nActivity: How do bees pick up pollen in flowers?\nActivity: How do bees pick up pollen in flowers?\nUnit 3: Energy\nUnit mastery: 0%\nKinetic energy\nKinetic energy\nKinetic energy\nUnderstand: kinetic energy\nApply: kinetic energy\nPotential energy\nPotential energy\nPotential energy\nUnderstand: potential energy\nApply: potential energy\nConservation of energy\nConservation of energy\nConservation of energy\nUnderstand: conservation of energy\nApply: conservation of energy\nActivity: Why doesn't a basketball bounce forever?\nActivity: Why doesn't a basketball bounce forever?\nUnit 4: Waves\nUnit mastery: 0%\nWave properties\nWave properties\nWave properties\nUnderstand: wave properties\nApply: wave properties\nSound waves\nSound waves\nUnderstand: sound waves\nHuman ear\nElectromagnetic waves\nThe electromagnetic spectrum\nElectromagnetic waves and matter\nElectromagnetic waves\nUnderstand: electromagnetic waves\nApply: electromagnetic waves\nHuman eye\nActivity: How can light interactions be used to create art?\nActivity: How can light interactions be used to create art?\nUnit 5: Explore physics through simulations\nMastery unavailable\nIntroduction to simulation-based learning\nIntroduction to simulation-based learning\nExplore conservation of energy through simulations\nConservation of energy\nPhET challenge: Conservation of energy\nUnit 6: Teacher resources\nMastery unavailable\nUnit guides\nHow to use our NGSS-aligned unit guides\nMiddle school physics unit guides\nHands-on physics activities\nIntroduction to hands-on science activities\nActivity: How can a skydiver fall safely?\nActivity: How do bees pick up pollen in flowers?\nActivity: Why doesn't a basketball bounce forever?\nActivity: How can light interactions be used to create art?\nUp next for you:\nCourse challenge\nTest your knowledge of the skills in this course.\nStart Course challenge\nCommunity questions","attrs_markdown":"[Skip to main content](https:\/\/www.khanacademy.org\/science\/ms-physics#main-content)\n\nIf you're seeing this message, it means we're having trouble loading external resources on our website.\n\nIf you're behind a web filter, please make sure that the domains \\*.kastatic.org and \\*.kasandbox.org are unblocked.\n\nExplore\n\nSelect a category to view its courses\n\nSearch\n\nDonate\n\n[Log in](https:\/\/www.khanacademy.org\/login?continue=%2Fscience%2Fms-physics)[Sign up](https:\/\/www.khanacademy.org\/signup?continue=%2Fscience%2Fms-physics)\n\n[Search for courses, skills, and videos](https:\/\/www.khanacademy.org\/search)\n\n## Welcome to Khan Academy\\!\nSo we can give you the right tools, let us know if you're a...\n\nLearner\n\nTeacher\n\nParent\n\n[![](https:\/\/cdn.kastatic.org\/genfiles\/topic-icons\/icons\/physics_wave.png-6aa903-128c.png)Middle school physics6 units · 22 skills](https:\/\/www.khanacademy.org\/science\/ms-physics)\n\n[Unit 1Motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces)\n\n[Unit 2Non-contact interactions](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions)\n\n[Unit 3Energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy)\n\n[Unit 4Waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves)\n\n[Unit 5Explore physics through simulations](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations)\n\n[Unit 6Teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\n\nCourse challenge\n\nTest your knowledge of the skills in this course.[Start Course challenge](https:\/\/www.khanacademy.org\/science\/ms-physics\/test\/x1baed5db7c1bb50b:course-challenge)\n\n1. [Science](https:\/\/www.khanacademy.org\/science)\n# Middle school physics\n2,100 possible mastery points\n\nMastered\n\nProficient\n\nFamiliar\n\nAttempted\n\nNot started\n\nQuiz\n\nUnit test\n\n1. [Unit 1Unit 1: Motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces)\n   1. [Understand: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/understand-representing-motion)\n   2. [Apply: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/apply-motion)\n   3. [Understand: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/understand-action-and-reaction-forces)\n   4. [Apply: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/apply-forces-and-newton-s-third-law)\n   5. [Motion and forces: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/quiz\/x1baed5db7c1bb50b:motion-and-forces-quiz-1)\n   6. [Understand: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/understand-forces-and-acceleration)\n   7. [Apply: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/apply-forces-and-acceleration)\n   8. [Motion and forces: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/quiz\/x1baed5db7c1bb50b:motion-and-forces-quiz-2)\n   9. [Motion and forces: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/test\/x1baed5db7c1bb50b:motion-and-forces-unit-test)\n2. [Unit 2Unit 2: Non-contact interactions](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions)\n   1. [Understand: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/understand-gravitational-forces)\n   2. [Apply: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/apply-gravitational-force)\n   3. [Non-contact interactions: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities\/quiz\/x1baed5db7c1bb50b:non-contact-interactions-quiz-1)\n   4. [Understand: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-magnetic-forces)\n   5. [Apply: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-electromagnetism)\n   6. [Non-contact interactions: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/quiz\/x1baed5db7c1bb50b:non-contact-interactions-quiz-2)\n   7. [Non-contact interactions: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/test\/x1baed5db7c1bb50b:non-contact-interactions-unit-test)\n3. [Unit 3Unit 3: Energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy)\n   1. [Understand: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/understand-kinetic-energy)\n   2. [Apply: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/apply-kineticenergy)\n   3. [Understand: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/understand-potential-energy)\n   4. [Apply: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/apply-potentialenergy)\n   5. [Energy: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/quiz\/x1baed5db7c1bb50b:energy-quiz-1)\n   6. [Understand: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/understand-changes-in-energy)\n   7. [Apply: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/apply-changes-in-energy)\n   8. [Energy: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/quiz\/x1baed5db7c1bb50b:energy-quiz-2)\n   9. [Energy: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/test\/x1baed5db7c1bb50b:energy-unit-test)\n4. [Unit 4Unit 4: Waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves)\n   1. [Understand: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/understand-wave-properties)\n   2. [Apply: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/apply-wave-properties)\n   3. [Understand: sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/e\/understand-sound-waves)\n   4. [Waves: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/quiz\/x1baed5db7c1bb50b:waves-quiz-1)\n   5. [Understand: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/understand-absorption-and-reflection)\n   6. [Apply: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/apply-absorption-and-reflection)\n   7. [Waves: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/quiz\/x1baed5db7c1bb50b:waves-quiz-2)\n   8. [Waves: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/test\/x1baed5db7c1bb50b:waves-unit-test)\n5. [Unit 5Unit 5: Explore physics through simulations](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations)\n   This unit's exercises do not count toward course mastery.\n6. [Unit 6Unit 6: Teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\n   This unit does not include exercises.\n7. Course challenge\n   \n   Test your knowledge of the skills in this course.[Start Course challenge](https:\/\/www.khanacademy.org\/science\/ms-physics\/test\/x1baed5db7c1bb50b:course-challenge)\n\n## Welcome to middle school physics\\!\n[Watch an introduction video![](https:\/\/cdn.kastatic.org\/ka_thumbnails_cache\/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2:252 minutes 25 seconds](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. *This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https:\/\/www.khanacademy.org\/science\/highschool-physics) course.*\n\n‍\n\n[Give us feedback on this course](https:\/\/docs.google.com\/forms\/d\/e\/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g\/viewform?usp=sf_link)\n\n‍\n\n**Teaching this course? Check out our [teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\\!**\n\n[Learn more](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n## Welcome to middle school physics\\!\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. *This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https:\/\/www.khanacademy.org\/science\/highschool-physics) course.*\n\n‍\n\n[Give us feedback on this course](https:\/\/docs.google.com\/forms\/d\/e\/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g\/viewform?usp=sf_link)\n\n‍\n\n**Teaching this course? Check out our [teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\\!**\n\n[Learn more](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n[Watch an introduction video![](https:\/\/cdn.kastatic.org\/ka_thumbnails_cache\/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2:252 minutes 25 seconds](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n[Unit 1: Motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces)\n\nUnit mastery: 0%\n\n### Motion\n1. [Introduction to middle school physics](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n2. [Speed and velocity](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/speed-and-velocity)\n3. [Acceleration](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/ms-acceleration)\n4. [Reference frames](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/reference-frames)\n5. [Describing motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/a\/describing-motion)\n6. [Understand: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/understand-representing-motion)\n7. [Apply: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/apply-motion)\n\n### Forces\n1. [Forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/v\/forces)\n2. [Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/v\/newtons-third-law)\n3. [Forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/a\/forces-and-newtons-third-law)\n4. [Understand: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/understand-action-and-reaction-forces)\n5. [Apply: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/apply-forces-and-newton-s-third-law)\n\n### Connecting motion and forces\n1. [Newton's first law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/v\/newtons-first-law)\n2. [Newton's second law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/v\/newtons-second-law)\n3. [Connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/a\/forces-and-acceleration)\n4. [Understand: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/understand-forces-and-acceleration)\n5. [Apply: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/apply-forces-and-acceleration)\n\n[Unit 2: Non-contact interactions](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions)\n\nUnit mastery: 0%\n\n### Gravitational force\n1. [Gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/v\/gravitational-force)\n2. [Gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/a\/gravitational-forces)\n3. [Understand: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/understand-gravitational-forces)\n4. [Apply: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/apply-gravitational-force)\n\n### Activity: How can a skydiver fall safely?\n1. [Activity: How can a skydiver fall safely?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities\/a\/activity-how-can-a-skydiver-fall-safely)\n\n### Electric and magnetic forces\n1. [Electric force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/v\/electric-force)\n2. [Magnetic force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/v\/magnetic-force)\n3. [Electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/a\/electromagnetism)\n4. [Understand: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-magnetic-forces)\n5. [Apply: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-electromagnetism)\n\n### Activity: How do bees pick up pollen in flowers?\n1. [Activity: How do bees pick up pollen in flowers?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/a\/activity-how-do-bees-pick-up-pollen-in-flowers)\n\n[Unit 3: Energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy)\n\nUnit mastery: 0%\n\n### Kinetic energy\n1. [Kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/v\/ms-kinetic-energy)\n2. [Kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/a\/kinetic-energy)\n3. [Understand: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/understand-kinetic-energy)\n4. [Apply: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/apply-kineticenergy)\n\n### Potential energy\n1. [Potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/v\/ms-potential-energy)\n2. [Potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/a\/potential-energy)\n3. [Understand: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/understand-potential-energy)\n4. [Apply: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/apply-potentialenergy)\n\n### Conservation of energy\n1. [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/v\/ms-conservation-of-energy)\n2. [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/a\/changes-in-energy)\n3. [Understand: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/understand-changes-in-energy)\n4. [Apply: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/apply-changes-in-energy)\n\n### Activity: Why doesn't a basketball bounce forever?\n1. [Activity: Why doesn't a basketball bounce forever?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/a\/activity-why-doesn-t-a-basketball-bounce-forever)\n\n[Unit 4: Waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves)\n\nUnit mastery: 0%\n\n### Wave properties\n1. [Wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/v\/wave-properties)\n2. [Wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/a\/wave-properties)\n3. [Understand: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/understand-wave-properties)\n4. [Apply: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/apply-wave-properties)\n\n### Sound waves\n1. [Sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/v\/sound-waves)\n2. [Understand: sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/e\/understand-sound-waves)\n3. [Human ear](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/v\/human-ear-structure-working)\n\n### Electromagnetic waves\n1. [The electromagnetic spectrum](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/the-electromagnetic-spectrum)\n2. [Electromagnetic waves and matter](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/electromagnetic-waves-and-matter)\n3. [Electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/a\/electromagnetic-waves)\n4. [Understand: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/understand-absorption-and-reflection)\n5. [Apply: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/apply-absorption-and-reflection)\n6. [Human eye](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/structure-of-human-eye)\n\n### Activity: How can light interactions be used to create art?\n1. [Activity: How can light interactions be used to create art?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/a\/activity-how-can-light-interactions-be-used-to-create-art)\n\n[Unit 5: Explore physics through simulations](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations)\n\nMastery unavailable\n\n### Introduction to simulation-based learning\n1. [Introduction to simulation-based learning](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:introduction-to-simulation-based-learning\/a\/introduction-to-simulation-based-learning)\n\n### Explore conservation of energy through simulations\n1. [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations\/a\/changes-in-energy)\n2. [PhET challenge: Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations\/e\/phet-simulation-exploring-conservation-of-energy)\n\n[Unit 6: Teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\n\nMastery unavailable\n\n### Unit guides\n1. [How to use our NGSS-aligned unit guides](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:unit-guides\/a\/how-to-use-our-ngss-aligned-unit-guides)\n2. [Middle school physics unit guides](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:unit-guides\/a\/middle-school-physics-unit-guides)\n\n### Hands-on physics activities\n1. [Introduction to hands-on science activities](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/introduction-to-hands-on-science-activities)\n2. [Activity: How can a skydiver fall safely?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-can-a-skydiver-fall-safely)\n3. [Activity: How do bees pick up pollen in flowers?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-do-bees-pick-up-pollen-in-flowers)\n4. [Activity: Why doesn't a basketball bounce forever?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-why-doesn-t-a-basketball-bounce-forever)\n5. [Activity: How can light interactions be used to create art?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-can-light-interactions-be-used-to-create-art)\n\nUp next for you:Course challengeTest your knowledge of the skills in this course.[Start Course challenge](https:\/\/www.khanacademy.org\/science\/ms-physics\/test\/x1baed5db7c1bb50b:course-challenge)\n\n[Community questions](https:\/\/www.khanacademy.org\/science\/ms-physics\/d)\n\nOur mission is to provide a free, world-class education to anyone, anywhere.\n\nKhan Academy is a 501(c)(3) nonprofit organization. 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[Science](https:\/\/www.khanacademy.org\/science)\n\n2,100 possible mastery points\n\nMastered\n\nProficient\n\nFamiliar\n\nAttempted\n\nNot started\n\nQuiz\n\nUnit test\n\n1. [Unit 1Unit 1: Motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces)\n   1. [Understand: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/understand-representing-motion)\n   2. [Apply: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/apply-motion)\n   3. [Understand: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/understand-action-and-reaction-forces)\n   4. [Apply: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/apply-forces-and-newton-s-third-law)\n   5. [Motion and forces: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/quiz\/x1baed5db7c1bb50b:motion-and-forces-quiz-1)\n   6. [Understand: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/understand-forces-and-acceleration)\n   7. [Apply: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/apply-forces-and-acceleration)\n   8. [Motion and forces: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/quiz\/x1baed5db7c1bb50b:motion-and-forces-quiz-2)\n   9. [Motion and forces: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/test\/x1baed5db7c1bb50b:motion-and-forces-unit-test)\n2. [Unit 2Unit 2: Non-contact interactions](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions)\n   1. [Understand: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/understand-gravitational-forces)\n   2. [Apply: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/apply-gravitational-force)\n   3. [Non-contact interactions: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities\/quiz\/x1baed5db7c1bb50b:non-contact-interactions-quiz-1)\n   4. [Understand: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-magnetic-forces)\n   5. [Apply: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-electromagnetism)\n   6. [Non-contact interactions: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/quiz\/x1baed5db7c1bb50b:non-contact-interactions-quiz-2)\n   7. [Non-contact interactions: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/test\/x1baed5db7c1bb50b:non-contact-interactions-unit-test)\n3. [Unit 3Unit 3: Energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy)\n   1. [Understand: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/understand-kinetic-energy)\n   2. [Apply: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/apply-kineticenergy)\n   3. [Understand: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/understand-potential-energy)\n   4. [Apply: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/apply-potentialenergy)\n   5. [Energy: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/quiz\/x1baed5db7c1bb50b:energy-quiz-1)\n   6. [Understand: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/understand-changes-in-energy)\n   7. [Apply: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/apply-changes-in-energy)\n   8. [Energy: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/quiz\/x1baed5db7c1bb50b:energy-quiz-2)\n   9. [Energy: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/test\/x1baed5db7c1bb50b:energy-unit-test)\n4. [Unit 4Unit 4: Waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves)\n   1. [Understand: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/understand-wave-properties)\n   2. [Apply: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/apply-wave-properties)\n   3. [Understand: sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/e\/understand-sound-waves)\n   4. [Waves: Quiz 1](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/quiz\/x1baed5db7c1bb50b:waves-quiz-1)\n   5. [Understand: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/understand-absorption-and-reflection)\n   6. [Apply: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/apply-absorption-and-reflection)\n   7. [Waves: Quiz 2](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/quiz\/x1baed5db7c1bb50b:waves-quiz-2)\n   8. [Waves: Unit test](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/test\/x1baed5db7c1bb50b:waves-unit-test)\n5. [Unit 5Unit 5: Explore physics through simulations](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations)\n   This unit's exercises do not count toward course mastery.\n6. [Unit 6Unit 6: Teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\n   This unit does not include exercises.\n7. Course challenge\n   \n   Test your knowledge of the skills in this course.[Start Course challenge](https:\/\/www.khanacademy.org\/science\/ms-physics\/test\/x1baed5db7c1bb50b:course-challenge)\n\n## Welcome to middle school physics\\!\n[Watch an introduction video![](https:\/\/cdn.kastatic.org\/ka_thumbnails_cache\/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2 minutes 25 seconds](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. *This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https:\/\/www.khanacademy.org\/science\/highschool-physics) course.*  \n  [Give us feedback on this course](https:\/\/docs.google.com\/forms\/d\/e\/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g\/viewform?usp=sf_link)  \n **Teaching this course? Check out our [teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\\!**\n\n[Learn more](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n## Welcome to middle school physics\\!\nLearn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. *This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https:\/\/www.khanacademy.org\/science\/highschool-physics) course.*  \n  [Give us feedback on this course](https:\/\/docs.google.com\/forms\/d\/e\/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g\/viewform?usp=sf_link)  \n **Teaching this course? Check out our [teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources)\\!**\n\n[Learn more](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n[Watch an introduction video![](https:\/\/cdn.kastatic.org\/ka_thumbnails_cache\/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2 minutes 25 seconds](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics)\n\n[Unit 1: Motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces) Unit mastery: 0% Motion [Introduction to middle school physics](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/intro-to-middle-school-physics) [Speed and velocity](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/speed-and-velocity) [Acceleration](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/ms-acceleration) [Reference frames](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/v\/reference-frames) [Describing motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/a\/describing-motion) [Understand: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/understand-representing-motion) [Apply: motion](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:motion\/e\/apply-motion) Forces [Forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/v\/forces) [Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/v\/newtons-third-law) [Forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/a\/forces-and-newtons-third-law) [Understand: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/understand-action-and-reaction-forces) [Apply: forces and Newton's third law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:forces\/e\/apply-forces-and-newton-s-third-law) Connecting motion and forces [Newton's first law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/v\/newtons-first-law) [Newton's second law](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/v\/newtons-second-law) [Connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/a\/forces-and-acceleration) [Understand: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/understand-forces-and-acceleration) [Apply: connecting motion and forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:motion-and-forces\/x1baed5db7c1bb50b:connecting-motion-and-forces\/e\/apply-forces-and-acceleration) [Unit 2: Non-contact interactions](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions) Unit mastery: 0% Gravitational force [Gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/v\/gravitational-force) [Gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/a\/gravitational-forces) [Understand: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/understand-gravitational-forces) [Apply: gravitational force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:gravitational-force\/e\/apply-gravitational-force) Activity: How can a skydiver fall safely? [Activity: How can a skydiver fall safely?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities\/a\/activity-how-can-a-skydiver-fall-safely) Electric and magnetic forces [Electric force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/v\/electric-force) [Magnetic force](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/v\/magnetic-force) [Electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/a\/electromagnetism) [Understand: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-magnetic-forces) [Apply: electric and magnetic forces](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:electric-and-magnetic-forces\/e\/understand-electromagnetism) Activity: How do bees pick up pollen in flowers? [Activity: How do bees pick up pollen in flowers?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:non-contact-interactions\/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers\/a\/activity-how-do-bees-pick-up-pollen-in-flowers) [Unit 3: Energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy) Unit mastery: 0% Kinetic energy [Kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/v\/ms-kinetic-energy) [Kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/a\/kinetic-energy) [Understand: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/understand-kinetic-energy) [Apply: kinetic energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:kinetic-energy\/e\/apply-kineticenergy) Potential energy [Potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/v\/ms-potential-energy) [Potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/a\/potential-energy) [Understand: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/understand-potential-energy) [Apply: potential energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:potential-energy\/e\/apply-potentialenergy) Conservation of energy [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/v\/ms-conservation-of-energy) [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/a\/changes-in-energy) [Understand: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/understand-changes-in-energy) [Apply: conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:conservation-of-energy\/e\/apply-changes-in-energy) Activity: Why doesn't a basketball bounce forever? [Activity: Why doesn't a basketball bounce forever?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:energy\/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities\/a\/activity-why-doesn-t-a-basketball-bounce-forever) [Unit 4: Waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves) Unit mastery: 0% Wave properties [Wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/v\/wave-properties) [Wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/a\/wave-properties) [Understand: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/understand-wave-properties) [Apply: wave properties](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:wave-properties\/e\/apply-wave-properties) Sound waves [Sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/v\/sound-waves) [Understand: sound waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/e\/understand-sound-waves) [Human ear](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:sound-waves\/v\/human-ear-structure-working) Electromagnetic waves [The electromagnetic spectrum](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/the-electromagnetic-spectrum) [Electromagnetic waves and matter](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/electromagnetic-waves-and-matter) [Electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/a\/electromagnetic-waves) [Understand: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/understand-absorption-and-reflection) [Apply: electromagnetic waves](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/e\/apply-absorption-and-reflection) [Human eye](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:electromagnetic-waves\/v\/structure-of-human-eye) Activity: How can light interactions be used to create art? [Activity: How can light interactions be used to create art?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:waves\/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art\/a\/activity-how-can-light-interactions-be-used-to-create-art) [Unit 5: Explore physics through simulations](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations) Mastery unavailable Introduction to simulation-based learning [Introduction to simulation-based learning](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:introduction-to-simulation-based-learning\/a\/introduction-to-simulation-based-learning) Explore conservation of energy through simulations [Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations\/a\/changes-in-energy) [PhET challenge: Conservation of energy](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:explore-physics-through-simulations\/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations\/e\/phet-simulation-exploring-conservation-of-energy) [Unit 6: Teacher resources](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources) Mastery unavailable Unit guides [How to use our NGSS-aligned unit guides](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:unit-guides\/a\/how-to-use-our-ngss-aligned-unit-guides) [Middle school physics unit guides](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:unit-guides\/a\/middle-school-physics-unit-guides) Hands-on physics activities [Introduction to hands-on science activities](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/introduction-to-hands-on-science-activities) [Activity: How can a skydiver fall safely?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-can-a-skydiver-fall-safely) [Activity: How do bees pick up pollen in flowers?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-do-bees-pick-up-pollen-in-flowers) [Activity: Why doesn't a basketball bounce forever?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-why-doesn-t-a-basketball-bounce-forever) [Activity: How can light interactions be used to create art?](https:\/\/www.khanacademy.org\/science\/ms-physics\/x1baed5db7c1bb50b:teacher-resources\/x1baed5db7c1bb50b:hands-on-physics-activities\/a\/activity-how-can-light-interactions-be-used-to-create-art) Up next for you:Course challengeTest your knowledge of the skills in this course.[Start Course challenge](https:\/\/www.khanacademy.org\/science\/ms-physics\/test\/x1baed5db7c1bb50b:course-challenge)\n\n[Community questions](https:\/\/www.khanacademy.org\/science\/ms-physics\/d)","meta_canonical":null}

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URL	https://www.khanacademy.org/science/ms-physics
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Meta Title	Middle school physics \| Science \| Khan Academy
Meta Description	Learn physics using videos, articles, and NGSS-aligned practice exercises. Explore the fundamentals of motion and forces, non-contact interactions, energy, and waves.
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Boilerpipe Text	If you're seeing this message, it means we're having trouble loading external resources on our website. If you're behind a web filter, please make sure that the domains .kastatic.org and .kasandbox.org are unblocked. Select a category to view its courses Log in Sign up Search for courses, skills, and videos Welcome to Khan Academy! So we can give you the right tools, let us know if you're a... Middle school physics 6 units · 22 skills Unit 1 Motion and forces Unit 2 Non-contact interactions Unit 3 Energy Unit 4 Waves Unit 5 Explore physics through simulations Unit 6 Teacher resources Course challenge Test your knowledge of the skills in this course. Start Course challenge Science 2,100 possible mastery points Mastered Proficient Familiar Attempted Not started Quiz Unit test Unit 1 Unit 1: Motion and forces Understand: motion Apply: motion Understand: forces and Newton's third law Apply: forces and Newton's third law Motion and forces: Quiz 1 Understand: connecting motion and forces Apply: connecting motion and forces Motion and forces: Quiz 2 Motion and forces: Unit test Unit 2 Unit 2: Non-contact interactions Understand: gravitational force Apply: gravitational force Non-contact interactions: Quiz 1 Understand: electric and magnetic forces Apply: electric and magnetic forces Non-contact interactions: Quiz 2 Non-contact interactions: Unit test Unit 3 Unit 3: Energy Understand: kinetic energy Apply: kinetic energy Understand: potential energy Apply: potential energy Energy: Quiz 1 Understand: conservation of energy Apply: conservation of energy Energy: Quiz 2 Energy: Unit test Unit 4 Unit 4: Waves Understand: wave properties Apply: wave properties Understand: sound waves Waves: Quiz 1 Understand: electromagnetic waves Apply: electromagnetic waves Waves: Quiz 2 Waves: Unit test Unit 5 Unit 5: Explore physics through simulations This unit's exercises do not count toward course mastery. Unit 6 Unit 6: Teacher resources This unit does not include exercises. Course challenge Test your knowledge of the skills in this course. Start Course challenge Welcome to middle school physics! Watch an introduction video 2 minutes 25 seconds Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our high school physics course. Give us feedback on this course Teaching this course? Check out our teacher resources ! Learn more Welcome to middle school physics! Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our high school physics course. Give us feedback on this course Teaching this course? Check out our teacher resources ! Learn more Watch an introduction video 2 minutes 25 seconds Unit 1: Motion and forces Unit mastery: 0% Motion Introduction to middle school physics Speed and velocity Acceleration Reference frames Describing motion Understand: motion Apply: motion Forces Forces Newton's third law Forces and Newton's third law Understand: forces and Newton's third law Apply: forces and Newton's third law Connecting motion and forces Newton's first law Newton's second law Connecting motion and forces Understand: connecting motion and forces Apply: connecting motion and forces Unit 2: Non-contact interactions Unit mastery: 0% Gravitational force Gravitational force Gravitational force Understand: gravitational force Apply: gravitational force Activity: How can a skydiver fall safely? Activity: How can a skydiver fall safely? Electric and magnetic forces Electric force Magnetic force Electric and magnetic forces Understand: electric and magnetic forces Apply: electric and magnetic forces Activity: How do bees pick up pollen in flowers? Activity: How do bees pick up pollen in flowers? Unit 3: Energy Unit mastery: 0% Kinetic energy Kinetic energy Kinetic energy Understand: kinetic energy Apply: kinetic energy Potential energy Potential energy Potential energy Understand: potential energy Apply: potential energy Conservation of energy Conservation of energy Conservation of energy Understand: conservation of energy Apply: conservation of energy Activity: Why doesn't a basketball bounce forever? Activity: Why doesn't a basketball bounce forever? Unit 4: Waves Unit mastery: 0% Wave properties Wave properties Wave properties Understand: wave properties Apply: wave properties Sound waves Sound waves Understand: sound waves Human ear Electromagnetic waves The electromagnetic spectrum Electromagnetic waves and matter Electromagnetic waves Understand: electromagnetic waves Apply: electromagnetic waves Human eye Activity: How can light interactions be used to create art? Activity: How can light interactions be used to create art? Unit 5: Explore physics through simulations Mastery unavailable Introduction to simulation-based learning Introduction to simulation-based learning Explore conservation of energy through simulations Conservation of energy PhET challenge: Conservation of energy Unit 6: Teacher resources Mastery unavailable Unit guides How to use our NGSS-aligned unit guides Middle school physics unit guides Hands-on physics activities Introduction to hands-on science activities Activity: How can a skydiver fall safely? Activity: How do bees pick up pollen in flowers? Activity: Why doesn't a basketball bounce forever? Activity: How can light interactions be used to create art? Up next for you: Course challenge Test your knowledge of the skills in this course. Start Course challenge Community questions
Markdown	[Skip to main content](https://www.khanacademy.org/science/ms-physics#main-content) If you're seeing this message, it means we're having trouble loading external resources on our website. If you're behind a web filter, please make sure that the domains \.kastatic.org and \.kasandbox.org are unblocked. Explore Select a category to view its courses Search Donate [Log in](https://www.khanacademy.org/login?continue=%2Fscience%2Fms-physics)[Sign up](https://www.khanacademy.org/signup?continue=%2Fscience%2Fms-physics) [Search for courses, skills, and videos](https://www.khanacademy.org/search) ## Welcome to Khan Academy\! So we can give you the right tools, let us know if you're a... Learner Teacher Parent [![](https://cdn.kastatic.org/genfiles/topic-icons/icons/physics_wave.png-6aa903-128c.png)Middle school physics6 units · 22 skills](https://www.khanacademy.org/science/ms-physics) [Unit 1Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) [Unit 2Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) [Unit 3Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) [Unit 4Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) [Unit 5Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) [Unit 6Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) Course challenge Test your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) 1. [Science](https://www.khanacademy.org/science) # Middle school physics 2,100 possible mastery points Mastered Proficient Familiar Attempted Not started Quiz Unit test 1. [Unit 1Unit 1: Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) 1. [Understand: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/understand-representing-motion) 2. [Apply: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/apply-motion) 3. [Understand: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/understand-action-and-reaction-forces) 4. [Apply: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/apply-forces-and-newton-s-third-law) 5. [Motion and forces: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/quiz/x1baed5db7c1bb50b:motion-and-forces-quiz-1) 6. [Understand: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/understand-forces-and-acceleration) 7. [Apply: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/apply-forces-and-acceleration) 8. [Motion and forces: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/quiz/x1baed5db7c1bb50b:motion-and-forces-quiz-2) 9. [Motion and forces: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/test/x1baed5db7c1bb50b:motion-and-forces-unit-test) 2. [Unit 2Unit 2: Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) 1. [Understand: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/understand-gravitational-forces) 2. [Apply: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/apply-gravitational-force) 3. [Non-contact interactions: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities/quiz/x1baed5db7c1bb50b:non-contact-interactions-quiz-1) 4. [Understand: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-magnetic-forces) 5. [Apply: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-electromagnetism) 6. [Non-contact interactions: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/quiz/x1baed5db7c1bb50b:non-contact-interactions-quiz-2) 7. [Non-contact interactions: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/test/x1baed5db7c1bb50b:non-contact-interactions-unit-test) 3. [Unit 3Unit 3: Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) 1. [Understand: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/understand-kinetic-energy) 2. [Apply: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/apply-kineticenergy) 3. [Understand: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/understand-potential-energy) 4. [Apply: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/apply-potentialenergy) 5. [Energy: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/quiz/x1baed5db7c1bb50b:energy-quiz-1) 6. [Understand: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/understand-changes-in-energy) 7. [Apply: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/apply-changes-in-energy) 8. [Energy: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/quiz/x1baed5db7c1bb50b:energy-quiz-2) 9. [Energy: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/test/x1baed5db7c1bb50b:energy-unit-test) 4. [Unit 4Unit 4: Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) 1. [Understand: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/understand-wave-properties) 2. [Apply: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/apply-wave-properties) 3. [Understand: sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/e/understand-sound-waves) 4. [Waves: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/quiz/x1baed5db7c1bb50b:waves-quiz-1) 5. [Understand: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/understand-absorption-and-reflection) 6. [Apply: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/apply-absorption-and-reflection) 7. [Waves: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/quiz/x1baed5db7c1bb50b:waves-quiz-2) 8. [Waves: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/test/x1baed5db7c1bb50b:waves-unit-test) 5. [Unit 5Unit 5: Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) This unit's exercises do not count toward course mastery. 6. [Unit 6Unit 6: Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) This unit does not include exercises. 7. Course challenge Test your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) ## Welcome to middle school physics\! [Watch an introduction video![](https://cdn.kastatic.org/ka_thumbnails_cache/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2:252 minutes 25 seconds](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https://www.khanacademy.org/science/highschool-physics) course. ‍ [Give us feedback on this course](https://docs.google.com/forms/d/e/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g/viewform?usp=sf_link) ‍ Teaching this course? Check out our [teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources)\! [Learn more](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) ## Welcome to middle school physics\! Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https://www.khanacademy.org/science/highschool-physics) course. ‍ [Give us feedback on this course](https://docs.google.com/forms/d/e/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g/viewform?usp=sf_link) ‍ Teaching this course? Check out our [teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources)\! [Learn more](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) [Watch an introduction video![](https://cdn.kastatic.org/ka_thumbnails_cache/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2:252 minutes 25 seconds](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) [Unit 1: Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) Unit mastery: 0% ### Motion 1. [Introduction to middle school physics](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) 2. [Speed and velocity](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/speed-and-velocity) 3. [Acceleration](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/ms-acceleration) 4. [Reference frames](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/reference-frames) 5. [Describing motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/a/describing-motion) 6. [Understand: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/understand-representing-motion) 7. [Apply: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/apply-motion) ### Forces 1. [Forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/v/forces) 2. [Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/v/newtons-third-law) 3. [Forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/a/forces-and-newtons-third-law) 4. [Understand: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/understand-action-and-reaction-forces) 5. [Apply: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/apply-forces-and-newton-s-third-law) ### Connecting motion and forces 1. [Newton's first law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/v/newtons-first-law) 2. [Newton's second law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/v/newtons-second-law) 3. [Connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/a/forces-and-acceleration) 4. [Understand: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/understand-forces-and-acceleration) 5. [Apply: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/apply-forces-and-acceleration) [Unit 2: Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) Unit mastery: 0% ### Gravitational force 1. [Gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/v/gravitational-force) 2. [Gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/a/gravitational-forces) 3. [Understand: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/understand-gravitational-forces) 4. [Apply: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/apply-gravitational-force) ### Activity: How can a skydiver fall safely? 1. [Activity: How can a skydiver fall safely?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities/a/activity-how-can-a-skydiver-fall-safely) ### Electric and magnetic forces 1. [Electric force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/v/electric-force) 2. [Magnetic force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/v/magnetic-force) 3. [Electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/a/electromagnetism) 4. [Understand: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-magnetic-forces) 5. [Apply: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-electromagnetism) ### Activity: How do bees pick up pollen in flowers? 1. [Activity: How do bees pick up pollen in flowers?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/a/activity-how-do-bees-pick-up-pollen-in-flowers) [Unit 3: Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) Unit mastery: 0% ### Kinetic energy 1. [Kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/v/ms-kinetic-energy) 2. [Kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/a/kinetic-energy) 3. [Understand: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/understand-kinetic-energy) 4. [Apply: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/apply-kineticenergy) ### Potential energy 1. [Potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/v/ms-potential-energy) 2. [Potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/a/potential-energy) 3. [Understand: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/understand-potential-energy) 4. [Apply: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/apply-potentialenergy) ### Conservation of energy 1. [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/v/ms-conservation-of-energy) 2. [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/a/changes-in-energy) 3. [Understand: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/understand-changes-in-energy) 4. [Apply: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/apply-changes-in-energy) ### Activity: Why doesn't a basketball bounce forever? 1. [Activity: Why doesn't a basketball bounce forever?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/a/activity-why-doesn-t-a-basketball-bounce-forever) [Unit 4: Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) Unit mastery: 0% ### Wave properties 1. [Wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/v/wave-properties) 2. [Wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/a/wave-properties) 3. [Understand: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/understand-wave-properties) 4. [Apply: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/apply-wave-properties) ### Sound waves 1. [Sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/v/sound-waves) 2. [Understand: sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/e/understand-sound-waves) 3. [Human ear](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/v/human-ear-structure-working) ### Electromagnetic waves 1. [The electromagnetic spectrum](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/the-electromagnetic-spectrum) 2. [Electromagnetic waves and matter](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/electromagnetic-waves-and-matter) 3. [Electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/a/electromagnetic-waves) 4. [Understand: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/understand-absorption-and-reflection) 5. [Apply: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/apply-absorption-and-reflection) 6. [Human eye](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/structure-of-human-eye) ### Activity: How can light interactions be used to create art? 1. [Activity: How can light interactions be used to create art?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/a/activity-how-can-light-interactions-be-used-to-create-art) [Unit 5: Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) Mastery unavailable ### Introduction to simulation-based learning 1. [Introduction to simulation-based learning](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:introduction-to-simulation-based-learning/a/introduction-to-simulation-based-learning) ### Explore conservation of energy through simulations 1. [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations/a/changes-in-energy) 2. [PhET challenge: Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations/e/phet-simulation-exploring-conservation-of-energy) [Unit 6: Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) Mastery unavailable ### Unit guides 1. [How to use our NGSS-aligned unit guides](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:unit-guides/a/how-to-use-our-ngss-aligned-unit-guides) 2. [Middle school physics unit guides](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:unit-guides/a/middle-school-physics-unit-guides) ### Hands-on physics activities 1. [Introduction to hands-on science activities](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/introduction-to-hands-on-science-activities) 2. [Activity: How can a skydiver fall safely?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-can-a-skydiver-fall-safely) 3. [Activity: How do bees pick up pollen in flowers?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-do-bees-pick-up-pollen-in-flowers) 4. [Activity: Why doesn't a basketball bounce forever?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-why-doesn-t-a-basketball-bounce-forever) 5. [Activity: How can light interactions be used to create art?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-can-light-interactions-be-used-to-create-art) Up next for you:Course challengeTest your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) [Community questions](https://www.khanacademy.org/science/ms-physics/d) Our mission is to provide a free, world-class education to anyone, anywhere. Khan Academy is a 501(c)(3) nonprofit organization. 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Readable Markdown	If you're seeing this message, it means we're having trouble loading external resources on our website. If you're behind a web filter, please make sure that the domains \.kastatic.org and \.kasandbox.org are unblocked. Select a category to view its courses [Log in](https://www.khanacademy.org/login?continue=%2Fscience%2Fms-physics)[Sign up](https://www.khanacademy.org/signup?continue=%2Fscience%2Fms-physics) [Search for courses, skills, and videos](https://www.khanacademy.org/search) ## Welcome to Khan Academy\! So we can give you the right tools, let us know if you're a... [![](https://cdn.kastatic.org/genfiles/topic-icons/icons/physics_wave.png-6aa903-128c.png)Middle school physics6 units · 22 skills](https://www.khanacademy.org/science/ms-physics) [Unit 1Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) [Unit 2Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) [Unit 3Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) [Unit 4Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) [Unit 5Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) [Unit 6Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) Course challenge Test your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) 1. [Science](https://www.khanacademy.org/science) 2,100 possible mastery points Mastered Proficient Familiar Attempted Not started Quiz Unit test 1. [Unit 1Unit 1: Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) 1. [Understand: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/understand-representing-motion) 2. [Apply: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/apply-motion) 3. [Understand: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/understand-action-and-reaction-forces) 4. [Apply: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/apply-forces-and-newton-s-third-law) 5. [Motion and forces: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/quiz/x1baed5db7c1bb50b:motion-and-forces-quiz-1) 6. [Understand: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/understand-forces-and-acceleration) 7. [Apply: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/apply-forces-and-acceleration) 8. [Motion and forces: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/quiz/x1baed5db7c1bb50b:motion-and-forces-quiz-2) 9. [Motion and forces: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/test/x1baed5db7c1bb50b:motion-and-forces-unit-test) 2. [Unit 2Unit 2: Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) 1. [Understand: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/understand-gravitational-forces) 2. [Apply: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/apply-gravitational-force) 3. [Non-contact interactions: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities/quiz/x1baed5db7c1bb50b:non-contact-interactions-quiz-1) 4. [Understand: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-magnetic-forces) 5. [Apply: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-electromagnetism) 6. [Non-contact interactions: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/quiz/x1baed5db7c1bb50b:non-contact-interactions-quiz-2) 7. [Non-contact interactions: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/test/x1baed5db7c1bb50b:non-contact-interactions-unit-test) 3. [Unit 3Unit 3: Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) 1. [Understand: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/understand-kinetic-energy) 2. [Apply: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/apply-kineticenergy) 3. [Understand: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/understand-potential-energy) 4. [Apply: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/apply-potentialenergy) 5. [Energy: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/quiz/x1baed5db7c1bb50b:energy-quiz-1) 6. [Understand: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/understand-changes-in-energy) 7. [Apply: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/apply-changes-in-energy) 8. [Energy: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/quiz/x1baed5db7c1bb50b:energy-quiz-2) 9. [Energy: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/test/x1baed5db7c1bb50b:energy-unit-test) 4. [Unit 4Unit 4: Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) 1. [Understand: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/understand-wave-properties) 2. [Apply: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/apply-wave-properties) 3. [Understand: sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/e/understand-sound-waves) 4. [Waves: Quiz 1](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/quiz/x1baed5db7c1bb50b:waves-quiz-1) 5. [Understand: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/understand-absorption-and-reflection) 6. [Apply: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/apply-absorption-and-reflection) 7. [Waves: Quiz 2](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/quiz/x1baed5db7c1bb50b:waves-quiz-2) 8. [Waves: Unit test](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/test/x1baed5db7c1bb50b:waves-unit-test) 5. [Unit 5Unit 5: Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) This unit's exercises do not count toward course mastery. 6. [Unit 6Unit 6: Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) This unit does not include exercises. 7. Course challenge Test your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) ## Welcome to middle school physics\! [Watch an introduction video![](https://cdn.kastatic.org/ka_thumbnails_cache/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2 minutes 25 seconds](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https://www.khanacademy.org/science/highschool-physics) course. [Give us feedback on this course](https://docs.google.com/forms/d/e/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g/viewform?usp=sf_link) Teaching this course? Check out our [teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources)\! [Learn more](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) ## Welcome to middle school physics\! Learn how we can describe and predict the motion of objects. Explore fundamental interactions of nature which act through fields. Discover how energy manifests in different ways and is conserved. Investigate the properties of waves, including sound and electromagnetic waves. This course is aligned to the middle school Next Generation Science Standards (NGSS). If you’ve mastered this content and want to explore physics at the next level, we recommend our [high school physics](https://www.khanacademy.org/science/highschool-physics) course. [Give us feedback on this course](https://docs.google.com/forms/d/e/1FAIpQLSe1vm_mkPJQ2EYplMtUW4-XSk8cROpv2avVDqLiZyz1iSsC0g/viewform?usp=sf_link) Teaching this course? Check out our [teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources)\! [Learn more](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) [Watch an introduction video![](https://cdn.kastatic.org/ka_thumbnails_cache/0c6efe85-f547-4e6e-acad-76a8214ec013_1280_720_base.png)2 minutes 25 seconds](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) [Unit 1: Motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces) Unit mastery: 0% Motion [Introduction to middle school physics](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/intro-to-middle-school-physics) [Speed and velocity](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/speed-and-velocity) [Acceleration](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/ms-acceleration) [Reference frames](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/v/reference-frames) [Describing motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/a/describing-motion) [Understand: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/understand-representing-motion) [Apply: motion](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/apply-motion) Forces [Forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/v/forces) [Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/v/newtons-third-law) [Forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/a/forces-and-newtons-third-law) [Understand: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/understand-action-and-reaction-forces) [Apply: forces and Newton's third law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:forces/e/apply-forces-and-newton-s-third-law) Connecting motion and forces [Newton's first law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/v/newtons-first-law) [Newton's second law](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/v/newtons-second-law) [Connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/a/forces-and-acceleration) [Understand: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/understand-forces-and-acceleration) [Apply: connecting motion and forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:connecting-motion-and-forces/e/apply-forces-and-acceleration) [Unit 2: Non-contact interactions](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions) Unit mastery: 0% Gravitational force [Gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/v/gravitational-force) [Gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/a/gravitational-forces) [Understand: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/understand-gravitational-forces) [Apply: gravitational force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:gravitational-force/e/apply-gravitational-force) Activity: How can a skydiver fall safely? [Activity: How can a skydiver fall safely?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:unit-2-phenomenon-based-activities/a/activity-how-can-a-skydiver-fall-safely) Electric and magnetic forces [Electric force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/v/electric-force) [Magnetic force](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/v/magnetic-force) [Electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/a/electromagnetism) [Understand: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-magnetic-forces) [Apply: electric and magnetic forces](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:electric-and-magnetic-forces/e/understand-electromagnetism) Activity: How do bees pick up pollen in flowers? [Activity: How do bees pick up pollen in flowers?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:non-contact-interactions/x1baed5db7c1bb50b:activity-how-do-bees-pick-up-pollen-in-flowers/a/activity-how-do-bees-pick-up-pollen-in-flowers) [Unit 3: Energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy) Unit mastery: 0% Kinetic energy [Kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/v/ms-kinetic-energy) [Kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/a/kinetic-energy) [Understand: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/understand-kinetic-energy) [Apply: kinetic energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/apply-kineticenergy) Potential energy [Potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/v/ms-potential-energy) [Potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/a/potential-energy) [Understand: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/understand-potential-energy) [Apply: potential energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/apply-potentialenergy) Conservation of energy [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/v/ms-conservation-of-energy) [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/a/changes-in-energy) [Understand: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/understand-changes-in-energy) [Apply: conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/apply-changes-in-energy) Activity: Why doesn't a basketball bounce forever? [Activity: Why doesn't a basketball bounce forever?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:unit-3-phenomenon-based-activities/a/activity-why-doesn-t-a-basketball-bounce-forever) [Unit 4: Waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves) Unit mastery: 0% Wave properties [Wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/v/wave-properties) [Wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/a/wave-properties) [Understand: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/understand-wave-properties) [Apply: wave properties](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:wave-properties/e/apply-wave-properties) Sound waves [Sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/v/sound-waves) [Understand: sound waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/e/understand-sound-waves) [Human ear](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:sound-waves/v/human-ear-structure-working) Electromagnetic waves [The electromagnetic spectrum](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/the-electromagnetic-spectrum) [Electromagnetic waves and matter](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/electromagnetic-waves-and-matter) [Electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/a/electromagnetic-waves) [Understand: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/understand-absorption-and-reflection) [Apply: electromagnetic waves](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/e/apply-absorption-and-reflection) [Human eye](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:electromagnetic-waves/v/structure-of-human-eye) Activity: How can light interactions be used to create art? [Activity: How can light interactions be used to create art?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:waves/x1baed5db7c1bb50b:activity-how-can-light-interactions-be-used-to-create-art/a/activity-how-can-light-interactions-be-used-to-create-art) [Unit 5: Explore physics through simulations](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations) Mastery unavailable Introduction to simulation-based learning [Introduction to simulation-based learning](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:introduction-to-simulation-based-learning/a/introduction-to-simulation-based-learning) Explore conservation of energy through simulations [Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations/a/changes-in-energy) [PhET challenge: Conservation of energy](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:explore-physics-through-simulations/x1baed5db7c1bb50b:explore-conservation-of-energy-through-simulations/e/phet-simulation-exploring-conservation-of-energy) [Unit 6: Teacher resources](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources) Mastery unavailable Unit guides [How to use our NGSS-aligned unit guides](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:unit-guides/a/how-to-use-our-ngss-aligned-unit-guides) [Middle school physics unit guides](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:unit-guides/a/middle-school-physics-unit-guides) Hands-on physics activities [Introduction to hands-on science activities](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/introduction-to-hands-on-science-activities) [Activity: How can a skydiver fall safely?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-can-a-skydiver-fall-safely) [Activity: How do bees pick up pollen in flowers?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-do-bees-pick-up-pollen-in-flowers) [Activity: Why doesn't a basketball bounce forever?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-why-doesn-t-a-basketball-bounce-forever) [Activity: How can light interactions be used to create art?](https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-how-can-light-interactions-be-used-to-create-art) Up next for you:Course challengeTest your knowledge of the skills in this course.[Start Course challenge](https://www.khanacademy.org/science/ms-physics/test/x1baed5db7c1bb50b:course-challenge) [Community questions](https://www.khanacademy.org/science/ms-physics/d)
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