https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-energy/v/energy-intro-kinetic-potential-work-energy-physics-khan-academy 2020-06-23T07:22:40Z Energy intro (kinetic & potential) Let's explore what kinetic & potential energies are. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/u_-59Qmfsihpnz1XX5WMvkIgGbosPyOphG2aFqhLwFt_p3Kqxcfm0JxweGNHCCa8eK1fxyaPD91AF5LXioTQPVZ5 Energy intro (kinetic & potential) Let's explore what kinetic & potential energies are. https://cdn.kastatic.org/ka-youtube-converted/e-CAW3fN68M.mp4/e-CAW3fN68M.mp4 596 Energy https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/v/ms-kinetic-energy 2025-07-01T10:10:08.145512912Z Kinetic energy Kinetic energy is the energy an object has due to its motion. How much kinetic energy an object has depends on two factors: the mass of the object, and the speed of the object. We can analyze data to determine how kinetic energy depends on these two factors separately. If we keep the object's speed constant and increase its mass, the object's kinetic energy increases in a linear pattern. If we keep the object's mass constant and increase its speed, the object's kinetic energy increases in a nonlinear pattern. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/5433a557-a5a4-49b9-a67b-3b1fd4c6233d_1280_720_base.png Kinetic energy Kinetic energy is the energy an object has due to its motion. How much kinetic energy an object has depends on two factors: the mass of the object, and the speed of the object. We can analyze data to determine how kinetic energy depends on these two factors separately. If we keep the object's speed constant and increase its mass, the object's kinetic energy increases in a linear pattern. If we keep the object's mass constant and increase its speed, the object's kinetic energy increases in a nonlinear pattern. https://cdn.kastatic.org/ka-youtube-converted/FtymZWAOeC0.mp4/FtymZWAOeC0.mp4 413 Energy https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:energy/x6679aa2c65c01e53:kinetic-and-potential-energy/v/kinetic_energy 2024-07-01T11:54:52.194339821Z Kinetic energy Energy is a scalar quantity measured in joules (J). One form is kinetic energy, which is energy due to motion. An object's kinetic energy depends on its mass and its speed. Kinetic energy is defined mathematically as K=(1/2)mv^2. Any moving macroscopic object possesses kinetic energy. The particles in matter also possess kinetic energy, leading to macroscopic energy effects like thermal energy and sound. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/ddafe116-d030-4969-a478-613d4771e813_1280_720_base.png Kinetic energy Energy is a scalar quantity measured in joules (J). One form is kinetic energy, which is energy due to motion. An object's kinetic energy depends on its mass and its speed. Kinetic energy is defined mathematically as K=(1/2)mv^2. Any moving macroscopic object possesses kinetic energy. The particles in matter also possess kinetic energy, leading to macroscopic energy effects like thermal energy and sound. https://cdn.kastatic.org/ka-youtube-converted/eVW8X_TsBzE.mp4/eVW8X_TsBzE.mp4 710 Energy https://www.khanacademy.org/science/strengthened-shs-physics-1/x5eb5cea12d2cf683:kinematics/x5eb5cea12d2cf683:energy/v/kinetic-energy-ms 2024-01-04T21:41:56.674101033Z Kinetic energy Any object in motion has the property of kinetic energy. Simply put, kinetic energy is motion energy and depends on an object's mass and speed. As mass or speed increases, so does kinetic energy. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/d4e3b2b1-7484-493a-bf4c-06b9cd7099d9_1280_720_base.png Kinetic energy Any object in motion has the property of kinetic energy. Simply put, kinetic energy is motion energy and depends on an object's mass and speed. As mass or speed increases, so does kinetic energy. https://cdn.kastatic.org/ka-youtube-converted/QFDVhfYu8HU.mp4/QFDVhfYu8HU.mp4 246 Energy https://www.khanacademy.org/science/up-science-grade-6-revision-course-full-term/x017c12e57b64cfa8:week-3/x017c12e57b64cfa8:work-and-energy/v/kinetic-energy 2023-06-26T04:10:39.513125705Z Kinetic energy What kind of energy do moving objects have? Let's find out! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Kinetic energy What kind of energy do moving objects have? Let's find out! https://cdn.kastatic.org/ka-youtube-converted/VCYis8ruZdI.mp4/VCYis8ruZdI.mp4 172 Energy https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/a/kinetic-energy 2025-12-18T14:30:42.483744329Z Kinetic energy Learn about kinetic energy. Use interactive graphs to discover how an object's kinetic energy depends on its mass and speed. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-work-energy-and-power/in-in-class11-kinetic-energy-ap/a/kinetic-energy-ap1 2021-04-29T07:53:31Z Kinetic energy review Review the key concepts, equations, and skills for kinetic energy.  Understand how kinetic energy can't be negative but the change in kinetic energy can be negative. article https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/understand-kinetic-energy 2025-12-21T20:47:51.596633051Z Understand: kinetic energy Check your understanding of kinetic energy in this set of free practice questions. Khan Academy exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:kinetic-energy/e/apply-kineticenergy 2025-07-02T17:03:27.180918202Z Apply: kinetic energy Apply your knowledge of kinetic energy in this set of free practice questions. Molly Sauder exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/v/ms-potential-energy 2025-07-01T10:10:08.145512912Z Potential energy Potential energy is stored in a system of objects interacting through non-contact forces. Types include gravitational potential energy and electric potential energy. The amount of potential energy in a system depends on the distance between the interacting objects. When the distance between two attracting objects increases, the potential energy stored in the system increases. When the distance between two repelling objects increases, the potential energy stored in the system decreases. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/74ba4c31-d810-4429-8a43-c88e3a63eed2_1280_720_base.png Potential energy Potential energy is stored in a system of objects interacting through non-contact forces. Types include gravitational potential energy and electric potential energy. The amount of potential energy in a system depends on the distance between the interacting objects. When the distance between two attracting objects increases, the potential energy stored in the system increases. When the distance between two repelling objects increases, the potential energy stored in the system decreases. https://cdn.kastatic.org/ka-youtube-converted/5VVY0MSkrd0.mp4/5VVY0MSkrd0.mp4 514 Energy https://www.khanacademy.org/science/grade-6-science-snc-aligned/x19bc096754f0b9af:energy/x19bc096754f0b9af:kinetic-and-potential-energy/v/potential-energy-ms 2024-01-04T21:41:56.674101033Z Potential energy Potential energy is the stored energy in an object due to its position, properties, and forces acting on it. Common types of potential energy include gravitational, elastic, magnetic, and electric. These energies relate to an object's position or shape, and their potential to convert into kinetic energy. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/8b5e60cb-c0bd-4709-956e-a0fea4cfe30e_1280_720_base.png Potential energy Potential energy is the stored energy in an object due to its position, properties, and forces acting on it. Common types of potential energy include gravitational, elastic, magnetic, and electric. These energies relate to an object's position or shape, and their potential to convert into kinetic energy. https://cdn.kastatic.org/ka-youtube-converted/oGzwVYPxKjg.mp4/oGzwVYPxKjg.mp4 224 Energy https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:energy/x6679aa2c65c01e53:kinetic-and-potential-energy/v/potential_energy 2024-07-01T11:54:52.194339821Z Potential energy Potential energy exists in a system of interacting objects. The amount of potential energy depends on the objects' relative positions. If two objects attract gravitationally or electrically, potential energy increases as they get farther apart. If two objects repel electrically, potential energy increases as they get closer. Elastic and chemical potential energy are fundamentally the result of electric potential energy at the particle level. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/46e10d4b-da46-44f8-85c8-27c667a49882_1280_720_base.png Potential energy Potential energy exists in a system of interacting objects. The amount of potential energy depends on the objects' relative positions. If two objects attract gravitationally or electrically, potential energy increases as they get farther apart. If two objects repel electrically, potential energy increases as they get closer. Elastic and chemical potential energy are fundamentally the result of electric potential energy at the particle level. https://cdn.kastatic.org/ka-youtube-converted/aUrms3VFn0I.mp4/aUrms3VFn0I.mp4 840 Energy https://www.khanacademy.org/science/up-science-grade-6-revision-course-full-term/x017c12e57b64cfa8:week-3/x017c12e57b64cfa8:work-and-energy/v/potential-energy 2023-06-26T04:10:39.513125705Z Potential energy What kind of energy does a stretched rubber band, or a compressed spring have? Let's find out! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Potential energy What kind of energy does a stretched rubber band, or a compressed spring have? Let's find out! https://cdn.kastatic.org/ka-youtube-converted/V0lrc4kud2o.mp4/V0lrc4kud2o.mp4 259 Energy https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/a/potential-energy 2025-12-21T20:47:51.596633051Z Potential energy Learn how potential energy is stored in systems of objects that interact through gravitational, electric, or magnetic fields. Discover how changing the arrangement of objects in a system affects the system's potential energy. article https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-energy/v/gravitational-potential-energy-derivation-work-energy-physics-khan-academy 2020-06-23T07:22:42Z Gravitational potential energy derivation Let's derive expression for gravitational potential energy.  Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/P2qiltiVUzc3i3Ne1cvL7szFYmNjlGgr7Ts7ehpAv3kqvdMlC2PZeSKmqJtStob6K4UoTRQ4_SD2FYwOc4UMiHMl Gravitational potential energy derivation Let's derive expression for gravitational potential energy.  https://cdn.kastatic.org/ka-youtube-converted/BlQg-0WQk9k.mp4/BlQg-0WQk9k.mp4 506 Energy https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-energy/v/work-done-by-gravity-path-independent-work-energy-physics-khan-academy 2020-06-23T07:22:43Z Work done by gravity (path independent) Let's see why work done by gravity is path independent.  Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/MV0A7KWtHC2Eiqk7dCgL9eAJtUz9fiAU6p_x776tcHqSduitLCCQ67wDr-RVVmC-8vdGE6BCar8vXkK-Naf93ZTWGQ Work done by gravity (path independent) Let's see why work done by gravity is path independent.  https://cdn.kastatic.org/ka-youtube-converted/5xNVxec4cME.mp4/5xNVxec4cME.mp4 888 Energy https://www.khanacademy.org/science/strengthened-shs-physics-1/x5eb5cea12d2cf683:kinematics/x5eb5cea12d2cf683:energy/a/what-is-gravitational-potential-energy 2024-12-01T02:55:17.002478639Z Gravitational potential energy Learn what gravitational potential energy is and how to calculate it. article https://www.khanacademy.org/science/in-in-class-11-physics-cbse-hindi/in-in-11-work-energy-and-power-hindi/gravitational-potential-energy-and-conservative-forces-hindi/a/gravitational-potential-energy-ap-physics-1 2021-04-29T07:58:15Z Gravitational potential energy and conservative forces review Review the key concepts and equations for gravitational potential energy, conservative forces, and nonconservative forces. article https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/understand-potential-energy 2025-12-21T20:47:51.596633051Z Understand: potential energy Check your understanding of potential energy in this set of free practice questions. Khan Academy exercise https://www.khanacademy.org/science/ap-college-physics-1/xf557a762645cccc5:work-energy-and-power/xf557a762645cccc5:potential-energy/e/gravitational-potential-energy-ap-physics-1 2025-12-23T14:40:11.31866507Z Potential energy Check your understanding of potential energy in this set of free practice questions. Sean Boston exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:potential-energy/e/apply-potentialenergy 2025-12-21T20:47:51.596633051Z Apply: potential energy Apply your knowledge of potential energy in this set of free practice questions. Molly Sauder exercise https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-work-energy-theorem/v/work-energy-theorem-work-energy-physics-khan-academy 2020-06-23T07:22:42Z Work-energy theorem Let's explore the work-energy theorem.  Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/dPQMR_RqfLIUvXXHiDKG1Y1YakPkKDY--iEMg_t7etKN4rgawat8FtmGjoQHi1DNJACmgyHwT5opHHUwJeW8eYSe Work-energy theorem Let's explore the work-energy theorem.  https://cdn.kastatic.org/ka-youtube-converted/nnMirzeTepQ.mp4/nnMirzeTepQ.mp4 754 Energy https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-work-energy-theorem/v/work-done-from-kinetic-energy-solved-example-work-energy-physics-khan-academy 2020-06-23T07:22:41Z Work done from kinetic energy - solved example Let's calculate work done when velocities are given.  Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/Lr4wjflZdpQNyvbGyyvP2VCqiBT9XsioGyVM9jZbt8kqTQ_YFeLxFq9z23rE2cIqE_11f3u9MYUaNIeThvoWUSyh Work done from kinetic energy - solved example Let's calculate work done when velocities are given.  https://cdn.kastatic.org/ka-youtube-converted/LexvE1LV0aE.mp4/LexvE1LV0aE.mp4 512 Energy https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-work-energy-and-power/in-in-class11-work-energy-theorem/a/work-energy-theorem-ap1 2021-04-29T07:54:46Z Work-energy theorem review Review the key concepts, equations, and skills for the work-energy theorem.  Understand how the work-energy theorem only applies to the net work, not the work done by a single source. article https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-work-energy-and-power/in-in-class11-work-energy-theorem/e/work-energy-theorem-exercises-ap1 2026-03-25T13:20:47.939559562Z Calculating change in kinetic energy from a force Find the change in kinetic energy from a force using the work energy theorem. April Russell exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/v/ms-conservation-of-energy 2025-07-01T10:10:08.145512912Z Conservation of energy If a system is isolated so that no energy is enters or leaves the system, the total amount of energy in the system remains the same over time. Energy may convert between kinetic and potential, but the total amount is constant. If energy is transferred into or out of the system, the total energy of the system does change. Energy often transfers out of systems as sound and thermal energy. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/5340bfae-2573-455a-869e-47e2556e3015_1280_720_base.png Conservation of energy If a system is isolated so that no energy is enters or leaves the system, the total amount of energy in the system remains the same over time. Energy may convert between kinetic and potential, but the total amount is constant. If energy is transferred into or out of the system, the total energy of the system does change. Energy often transfers out of systems as sound and thermal energy. https://cdn.kastatic.org/ka-youtube-converted/Tf4A93763Bw.mp4/Tf4A93763Bw.mp4 429 Energy https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-law-of-conservation-of-energy/v/law-of-energy-conservation-work-energy-physics-khan-academy 2020-06-23T07:22:40Z Law of energy conservation Let's explore the law of conservation of energy. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/Dtwjx3fL56QdUjrIobviYke_J1wmHabfJEm_h2CdpfAizQQagC_-4KBdrfCSc-sO4I1bXrMg5PoNkcN18FG_ydst Law of energy conservation Let's explore the law of conservation of energy. https://cdn.kastatic.org/ka-youtube-converted/b7k1uw8_ZtY.mp4/b7k1uw8_ZtY.mp4 787 Energy https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-work-energy/in-in-law-of-conservation-of-energy/v/energy-conservation-solved-example-work-energy-physics-khan-academy 2025-01-02T23:26:09.730705957Z Conservation of energy examples Practice two problems involving conservation of energy. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/eRpthabXUxS0tL90GF6SUI-79UtdZNvlmE00dcZkj35A8cBbA7qGy78B1soTnD1NMeZEEAXPfHzfiAE_YriEEKGU Conservation of energy examples Practice two problems involving conservation of energy. https://cdn.kastatic.org/ka-youtube-converted/O-9BXpHcOdQ.mp4/O-9BXpHcOdQ.mp4 575 Energy https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:teacher-resources/x1baed5db7c1bb50b:hands-on-physics-activities/a/activity-why-doesn-t-a-basketball-bounce-forever 2026-02-27T18:00:31.886851552Z Activity: Why doesn't a basketball bounce forever? Make science come alive in your classroom with this free hands-on activity aligned to middle school standards. article https://www.khanacademy.org/science/teacher-resources-ngss-science-domain/x2811526c37de0eab:hands-on-science-activities/x2811526c37de0eab:high-school-physics-activities/a/activity-how-do-engineers-design-roller-coasters 2026-01-26T00:30:32.82909804Z Activity: How do engineers design roller coasters? Make science come alive in your classroom with this free hands-on activity aligned to high school standards. article https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:energy/x6679aa2c65c01e53:work-and-power/a/what-is-kinetic-energy 2025-08-01T20:15:54.060235323Z Translational kinetic energy and work Learn about translational kinetic energy and how it's related to work through the work-kinetic energy theorem. article https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/understand-changes-in-energy 2026-04-07T23:17:37.123726494Z Understand: conservation of energy Check your understanding of conservation of energy in this set of free practice questions. Khan Academy exercise https://www.khanacademy.org/science/ap-college-physics-1/xf557a762645cccc5:work-energy-and-power/xf557a762645cccc5:untitled-271/e/conservation-of-energy-law-ap-physics-1 2025-12-21T23:40:11.622015733Z Conservation of energy Practice applying conservation of energy in this set of free practice questions. Sean Boston exercise https://www.khanacademy.org/science/in-in-class-11-physics-cbse-hindi/in-in-11-work-energy-and-power-hindi/conservation-of-energy-hindi/e/conservation-of-energy-conceptual-exercises-ap1 2026-04-08T00:36:09.500768563Z Changes in energy Practice applying the conservation of energy to predict changes in kinetic energy, potential energy, and velocity. April Russell exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:energy/x1baed5db7c1bb50b:conservation-of-energy/e/apply-changes-in-energy 2026-04-07T23:36:17.218592739Z Apply: conservation of energy Apply your knowledge of conservation of energy in this set of free practice questions. Khan Academy exercise