https://www.khanacademy.org/science/revision-up-science-class-6-full-term/x00110b31861f2508:week-2/x00110b31861f2508:measurement-of-length-and-motion/v/correct-way-to-measure-length 2023-06-26T03:56:33.129173029Z Correct way to measure length Let's find out the correct way to measure length of objects! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Correct way to measure length Let's find out the correct way to measure length of objects! https://cdn.kastatic.org/ka-youtube-converted/I45BQxU1TnI.mp4/I45BQxU1TnI.mp4 190 Movement and speed https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-measurement-data/cc-2nd-measuring-length/v/measuring-lengths-2 2021-06-24T11:10:10Z Measuring lengths (cm, m) Sal measures objects with a ruler. video https://cdn.kastatic.org/googleusercontent/Zpj4S0EuH_qlFQnFunEKVVQenHG3CmG_aERCLtuftqDz17eMrAjcf0xWQ7QBQNw3vtW5zSbJ6jWjMmhKe7FMslo Measuring lengths (cm, m) Sal measures objects with a ruler. https://cdn.kastatic.org/ka-youtube-converted/muC7HMIEYDU.mp4/muC7HMIEYDU.mp4 280 Movement and speed https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-measurement-data/cc-2nd-measuring-length/e/measuring-lengths-2 2026-03-25T20:00:51.494577527Z Measure lengths (cm, m) Measure objects using a ruler. All lengths are measured in centimeters or meters. Sarah Ledon exercise https://www.khanacademy.org/math/cc-third-grade-math/time/elapsed-time/v/times-differences-math-3rd-grade-khan-academy 2021-05-07T00:21:38Z Time differences example Learn to find the difference between the times shown on two different analog clocks.  Lindsay Spears video https://cdn.kastatic.org/googleusercontent/lyjefdN4HXQcgT0wNU0bDZgLqdcTnDdFD8js913WAqigXzZ6O_WitdKg2apGMU1poyl1F8OL4QyiFtie0NIcPw80qw Time differences example Learn to find the difference between the times shown on two different analog clocks.  https://cdn.kastatic.org/ka-youtube-converted/PCPmpPV9KR0.mp4/PCPmpPV9KR0.mp4 260 Movement and speed https://www.khanacademy.org/math/cc-third-grade-math/time/elapsed-time/e/time-differences 2023-11-06T04:18:33.000779835Z Time differences (within 60 minutes) Practice finding the difference between times given on two analog clocks. Each time difference is less than 60 minutes. Sandy exercise https://www.khanacademy.org/math/cc-fourth-grade-math/imp-measurement-and-data-2/imp-time-2/e/time-differences--over-the-hour- 2026-04-30T18:30:41.846286703Z Time differences Practice finding the difference between times given on two analog clocks. Time differences cross over the hour. Lindsay exercise https://www.khanacademy.org/math/cc-third-grade-math/time/elapsed-time/e/telling-time-word-problems 2026-05-06T05:31:17.506778064Z Telling time word problems (within the hour) Solve a word problem to find the duration of an event.  Both analog or digital clocks are included. Lindsay Spears exercise https://www.khanacademy.org/math/cc-2nd-grade-math/x3184e0ec:money-and-time/cc-2nd-time/v/time-on-a-number-line 2021-04-03T21:31:52Z Time on a number line Sal tells time on a number line. Sal Khan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Time on a number line Sal tells time on a number line. https://cdn.kastatic.org/ka-youtube-converted/Rc2v8JdebwQ.mp4/Rc2v8JdebwQ.mp4 117 Movement and speed https://www.khanacademy.org/math/cc-third-grade-math/time/tell-time-on-number-line/e/telling-time-on-the-number-line 2026-04-30T18:30:41.846286703Z Tell time on the number line Match time of a number line to time on an analog or digital clock. Graph a given time on a number line. Lindsay exercise https://www.khanacademy.org/math/cc-third-grade-math/time/tell-time-on-number-line/v/telling-time-problems-with-number-line 2021-07-15T19:05:23Z Telling time with number line Sal uses a number line to tell time and find the duration of an event. video https://cdn.kastatic.org/googleusercontent/ZikGNqnrjCTN-UlCpw7jhRBG6W2PwQX20bcTM5pEnOk-i0A5avKgLlfIIlvNH5yGe9mHJF0JbmsLgsF10dKg3HM Telling time with number line Sal uses a number line to tell time and find the duration of an event. https://cdn.kastatic.org/ka-youtube-converted/DA2w8lRelIc.mp4/DA2w8lRelIc.mp4 404 Movement and speed https://www.khanacademy.org/math/cc-third-grade-math/time/tell-time-on-number-line/e/telling-time-word-problems-with-the-number-line 2026-04-07T22:59:30.107127435Z Time word problems with number line Use a number line to help solve elapsed time word problems. elizabeth exercise https://www.khanacademy.org/math/cc-third-grade-math/time/elapsed-time/v/time-to-leave-for-home 2021-07-15T19:05:23Z Time word problem: travel time Sal solves what time do you leave if you are traveling 39 minutes and need to be home at 6:15. Sal Khan video https://cdn.kastatic.org/googleusercontent/J31qJtEBhQy6uzHuJ9FBN5TYt9gTXsWw31UR6YkTqrH0-mgQ49UqRMLJzecBJvhLm_RDk3WAfiQcM0l7pRg9jTW2 Time word problem: travel time Sal solves what time do you leave if you are traveling 39 minutes and need to be home at 6:15. https://cdn.kastatic.org/ka-youtube-converted/kul2ZmVIQZk.mp4/kul2ZmVIQZk.mp4 249 Movement and speed https://www.khanacademy.org/math/cc-fourth-grade-math/imp-measurement-and-data-2/imp-time-2/e/telling-time-word-problems- 2026-04-07T23:55:07.30621384Z Telling time word problems Solve a word problem to find the duration of an event. Both analog or digital clocks are included. Time in the word problems crosses over the hour. Lindsay exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/v/position_velocity_speed 2024-11-07T15:12:48.053941755Z Position, velocity, and speed An object's position specifies how far the object is from a reference point, and in what direction. The rate that an object's position changes is called velocity. Average velocity is calculated as change in position divided by change in time. Position and velocity are vector quantities. Average speed is calculated as distance travelled divided by time. Speed and distance are scalar quantities with no direction. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/b42f4e45-f832-4988-bcea-732d1348b410_1280_720_base.png Position, velocity, and speed An object's position specifies how far the object is from a reference point, and in what direction. The rate that an object's position changes is called velocity. Average velocity is calculated as change in position divided by change in time. Position and velocity are vector quantities. Average speed is calculated as distance travelled divided by time. Speed and distance are scalar quantities with no direction. https://cdn.kastatic.org/ka-youtube-converted/vOipqtdR23s.mp4/vOipqtdR23s.mp4 624 Movement and speed https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-motion/in-in-distance-and-displacement/v/distance-and-displacement 2021-03-16T17:54:06Z Distance and displacement introduction An introduction to the difference between distance traveled and displacement. Sal Khan video https://cdn.kastatic.org/googleusercontent/U9J74WVkIOXos6qhHlUAv16EpAYOpl8ktgzg5xJHxG_HOrywVAAo0_X3bh26uHuhKZJwxe-IF_vSOJ-w9_Ojnizl Distance and displacement introduction An introduction to the difference between distance traveled and displacement. https://cdn.kastatic.org/ka-youtube-converted/vQCkYm3v3aA.mp4/vQCkYm3v3aA.mp4 254 Movement and speed https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/e/speed-and-velocity 2026-04-07T22:23:57.656416987Z Speed and Velocity LO: Speed and velocity Revathi exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/v/instantaneous-speed-and-velocity 2022-11-16T04:22:43.7414897Z Instantaneous speed and velocity Instantaneous speed is a measurement of how fast an object is moving at that particular moment. Instantaneous velocity is a vector quantity that includes both the speed and the direction in which the object is moving. Learn how to find an object’s instantaneous speed or velocity in three ways - by using calculus, by looking at the slope of a given point on a graph of an object’s rate vs. time, or by using kinematic formulas if the object’s acceleration is constant. David SantoPietro video https://cdn.kastatic.org/googleusercontent/FhLCZfA8g2adKxxacA__pdTAeJ_PD8gzSJMTMCIvwlZqwM6oBJ44hUwDFPz_ljBnyARk9Hc36nrZfm2V_rXRRhWi Instantaneous speed and velocity Instantaneous speed is a measurement of how fast an object is moving at that particular moment. Instantaneous velocity is a vector quantity that includes both the speed and the direction in which the object is moving. Learn how to find an object’s instantaneous speed or velocity in three ways - by using calculus, by looking at the slope of a given point on a graph of an object’s rate vs. time, or by using kinematic formulas if the object’s acceleration is constant. https://cdn.kastatic.org/ka-youtube-converted/pfTTHx9kCHk.mp4/pfTTHx9kCHk.mp4 278 Movement and speed https://www.khanacademy.org/science/bridge-course-class-11th-physics/x4c0d503cda725c32:motion/x4c0d503cda725c32:basics-of-motion/v/average-speed-velocity 2024-01-16T04:11:35.384208864Z Average speed & velocity Let's explore what average speed and average velocity are. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Average speed & velocity Let's explore what average speed and average velocity are. https://cdn.kastatic.org/ka-youtube-converted/4-WNdVvTG1s.mp4/4-WNdVvTG1s.mp4 387 Movement and speed https://www.khanacademy.org/science/soe-science/x423b020590943f16:motion/x423b020590943f16:speed-and-velocity/e/basic-average-velocity-and-speed 2023-09-23T12:57:16.615056478Z Basic: Average velocity and speed Practice calculating average velocity and speed from word problems when an object moves in one direction. vibhor exercise https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-motion/in-in-average-speed-and-average-velocity/v/average-speed-velocity-with-examples 2020-06-23T07:22:41Z Average speed & velocity (with examples) Let's learn what average speed & velocity are using some examples. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/GLrCC8C_Hq_p5p68zARNU98qlEcH8FYkS0Y0wJy04zgGz2GBLu9FMNjdq-miMc_9iEbmXFOeBu57BO9oTNaR8ruo3w Average speed & velocity (with examples) Let's learn what average speed & velocity are using some examples. https://cdn.kastatic.org/ka-youtube-converted/a451lmDKv9w.mp4/a451lmDKv9w.mp4 565 Movement and speed https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/e/average-velocity-and-speed 2026-05-11T04:40:42.021307954Z Average velocity and speed Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:describing-motion/e/understand-motion-variables 2026-05-22T02:50:56.444203687Z Understand: Motion variables Check your understanding of motion variables in this set of free practice questions. Emily Cizmas exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/e/understanding-velocity-and-speed 2022-09-02T10:08:12.365878162Z Understanding velocity and speed Let's solve some problems to test our understanding of the meaning of velocity and speed in Physics - both average and instantaneous. Aakash Bagga exercise https://www.khanacademy.org/science/ms-physics/x1baed5db7c1bb50b:motion-and-forces/x1baed5db7c1bb50b:motion/e/understand-representing-motion 2026-05-01T13:40:34.883034315Z Understand: Motion Check your understanding of motion this set of free, standards-aligned practice questions. Khan Academy exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-motion-in-a-straight-line/in-in-motion-in-a-straight-line-velocity-and-speed-from-graphs/a/what-is-velocity 2025-03-12T14:20:10.072734823Z What is velocity? Velocity or speed? Instantaneous or average? Keep building your physics vocabulary. article https://www.khanacademy.org/math/cc-fifth-grade-math/imp-geometry-3/imp-intro-to-the-coordinate-plane/v/introduction-to-the-coordinate-plane 2022-11-16T04:22:43.7414897Z Introduction to the coordinate plane When we use coordinates to locate a point on a coordinate plane, we use two numbers to specify the horizontal (x) and vertical (y) positions. The first number in a coordinate pair tells us how far to move left or right from the origin, while the second number tells us how far to move up or down. video https://cdn.kastatic.org/ka_thumbnails_cache/eb451b7b-1a3e-47f3-a9dc-f52f81d8c689_1280_720_base.png Introduction to the coordinate plane When we use coordinates to locate a point on a coordinate plane, we use two numbers to specify the horizontal (x) and vertical (y) positions. The first number in a coordinate pair tells us how far to move left or right from the origin, while the second number tells us how far to move up or down. https://cdn.kastatic.org/ka-youtube-converted/pAlq9fFwtus.mp4/pAlq9fFwtus.mp4 408 Movement and speed https://www.khanacademy.org/math/cc-fifth-grade-math/imp-geometry-3/imp-intro-to-the-coordinate-plane/e/graphing_points 2026-06-16T15:10:40.519857796Z Graph points Plot a given point on the coordinate plane. Ben Eater exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:distance-time-graphs/v/position-time-graphs 2021-04-11T13:57:32Z Position-time graphs Using position-time graphs and number lines to find displacement and distance traveled. video https://cdn.kastatic.org/googleusercontent/SLxBU6FZuFrIKrjYdy-KObABJBq1YmeNDppXCvGqPNzEwGTGvm4Xi1WmIzuVJKziFCTfhFsY5IgCDtIQJs-4f44 Position-time graphs Using position-time graphs and number lines to find displacement and distance traveled. https://cdn.kastatic.org/ka-youtube-converted/9XxzIoUQd78.mp4/9XxzIoUQd78.mp4 301 Movement and speed https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:distance-time-graphs/v/position-vs-time-graphs 2024-09-30T01:21:36.460262764Z Position vs. time graphs Learn how to interpret a position vs. time graph. Use a position vs. time graph to determine displacement, distance, average velocity, average speed, instantaneous velocity, and instantaneous speed. David SantoPietro video https://cdn.kastatic.org/googleusercontent/1DsLefTdqGsQSv9z5Ra868WeExzIeSzB98Al0R-9M9ZvodwUWYJVGoIGilLUbyn92EPYTEKpVV54Kxm8WuYtSGI Position vs. time graphs Learn how to interpret a position vs. time graph. Use a position vs. time graph to determine displacement, distance, average velocity, average speed, instantaneous velocity, and instantaneous speed. https://cdn.kastatic.org/ka-youtube-converted/GtoamALPOP0.mp4/GtoamALPOP0.mp4 920 Movement and speed https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-motion-in-a-straight-line/in-in-motion-in-a-straight-line-codistance-displacement-and-coordinate-systems/v/examples-interpreting-position-time-graphs 2021-03-19T16:21:23Z Worked example: distance and displacement from position-time graphs Worked examples finding displacement and distance from position-time graphs. video https://cdn.kastatic.org/googleusercontent/muuQaP3qLmk-4UG3XOL_yGwzAd2n0flU9swT_9KnZ_DKhuWsd-_hGIW2Wde1KfVwaDaYMy6Q9_9QyJgZwP7Uvg4 Worked example: distance and displacement from position-time graphs Worked examples finding displacement and distance from position-time graphs. https://cdn.kastatic.org/ka-youtube-converted/az6i2qvI1E0.mp4/az6i2qvI1E0.mp4 544 Movement and speed https://www.khanacademy.org/science/in-in-class-11-physics-cbse-hindi/in-in-11-motion-in-a-straight-line-hindi/distance-displacement-and-coordinate-systems-hindi/e/yj-physics-exercise-1 2024-08-28T11:57:50.039372168Z Distance and displacement from graphs Practice calculating distance traveled and displacement from position vs. time graphs. Yuki exercise https://www.khanacademy.org/science/soe-science/x423b020590943f16:motion/x423b020590943f16:position-time-graphs/e/basic-finding-distance-and-displacement-from-position-time-graphs 2023-09-23T12:57:16.615056478Z Basic: Finding distance and displacement from position-time graphs Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:distance-time-graphs/e/finding-distance-and-displacement-from-position-time-graph-in 2025-04-09T10:12:02.040424533Z Finding distance and displacement from position-time graph Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-motion/in-in-position-time-graphs/v/position-time-graphs-class-9 2021-04-06T14:32:19Z Position-time graphs Using animations lets learn what position time graphs are, and how they help us figure out which objects are slower and faster. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/CpQ7Ya2V7QQQ_1PVHBS-BEF5SB4bwTwByGBFfLH9qliprwEMaZ7ETx8MqF3uBK3KPc9KM20YZDMMJRyPIob1mHvGIw Position-time graphs Using animations lets learn what position time graphs are, and how they help us figure out which objects are slower and faster. https://cdn.kastatic.org/ka-youtube-converted/7CHvM-VfoL8.mp4/7CHvM-VfoL8.mp4 716 Movement and speed https://www.khanacademy.org/science/soe-science/x423b020590943f16:motion/x423b020590943f16:position-time-graphs/e/advanced-position-time-graphs 2026-04-08T01:15:04.085520103Z Advanced: Position-time graphs Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/in-in-class9th-physics-india/in-in-motion/in-in-position-time-graphs/v/calc-velocity-from-position-time-graphs 2020-06-23T07:22:41Z Calc. velocity from position time graphs Let's learn how to calculate velocities from position-time graphs. We will also get some intuition behind why slope or steepness of position time graphs represent velocity. Mahesh Shenoy video https://cdn.kastatic.org/googleusercontent/K7jWjPMLDSNmfBZuRWPIksZsAD0OmSelNQHSx8aOP1WCur091H0rxY5-HhKpAeMptHtx94mIitF7i7p_l-MZ9fOC Calc. velocity from position time graphs Let's learn how to calculate velocities from position-time graphs. We will also get some intuition behind why slope or steepness of position time graphs represent velocity. https://cdn.kastatic.org/ka-youtube-converted/7kHOA0o9TzQ.mp4/7kHOA0o9TzQ.mp4 569 Movement and speed https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:distance-time-graphs/e/basic-average-speed-and-average-velocity-from-graphs 2023-09-23T12:57:16.615056478Z Basic: Average speed and average velocity from graphs Let's solve some questions! vibhor exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:distance-time-graphs/a/position-vs-time-graphs 2026-06-30T19:30:53.53192136Z Learn and try: Position vs. time graphs Learn how to interpret the motion of an object represented on a position vs. time graph. article https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:describing-motion/v/interpreting_motion_data 2024-06-21T18:55:31.273097146Z Interpreting motion data The same motion data can be presented in various ways, including dot (oil drop) diagrams, position-time tables, and position vs. time graphs. The slope of a position vs. time graph represents the object's velocity: A straight line (constant slope) means the object moved with constant velocity, and a curved line (changing slope) means the object accelerated. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/173ff128-6009-44d0-848c-3e7efb53454b_1280_720_base.png Interpreting motion data The same motion data can be presented in various ways, including dot (oil drop) diagrams, position-time tables, and position vs. time graphs. The slope of a position vs. time graph represents the object's velocity: A straight line (constant slope) means the object moved with constant velocity, and a curved line (changing slope) means the object accelerated. https://cdn.kastatic.org/ka-youtube-converted/-1xbgz26ZNs.mp4/-1xbgz26ZNs.mp4 606 Movement and speed https://www.khanacademy.org/science/highschool-physics/x6679aa2c65c01e53:motion-and-forces/x6679aa2c65c01e53:describing-motion/e/apply-constant-speed-motion 2026-05-22T02:50:56.444203687Z Apply: Constant speed motion Apply your knowledge of constant speed motion in this set of free practice questions. Emily Cizmas exercise https://www.khanacademy.org/math/ap-calculus-ab/ab-diff-contextual-applications-new/ab-4-2/e/interpret-motion-graphs 2021-04-29T08:01:41Z Interpret motion graphs Interpret graphs that describe motion along a line. Tomer Gal exercise https://www.khanacademy.org/science/in-in-class11th-physics/in-in-class11th-physics-motion-in-a-straight-line/in-in-motion-in-a-straight-line-velocity-and-speed-from-graphs/a/average-velocity-speed-w-graphs 2021-04-29T07:48:21Z Instantaneous velocity and speed from graphs review Review the key terms and skills related to analyzing motion graphs, such as finding velocity from position vs. time graphs and displacement from velocity vs. time graphs. article https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinematics/x0e04e0cb682fb793:speed-and-velocity/e/visual-representations-of-motion 2026-06-19T17:56:42.733541135Z Visual representations of motion Check your understanding of visual representations of motion in this set of free practice questions. Molly exercise