About Lesson
Path Length (Distance) Vs. Displacement
Path Length: It is the distance between two points along a straight line. It is scalar quantity.
Displacement: It is the change in position in a particular time interval. It is vector quantity. Change is position is usually denoted by Δx (x2-x1) and change in time is denoted by Δt (t2-t1).
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Position-Time, Velocity-Time and Acceleration-Time Graph
Criteria | P-T Graph | V-T Graph | A-T Graph |
X and Y axis | Time and Position | Time and Velocity | Time and Acceleration |
Slope | It represents velocity of an object | It represents acceleration of an object. | It represents the jerk or push of a moving object. |
Straight slope | Uniform velocity | Uniform acceleration | Uniform jerk |
Curvy Slope | Change in velocity | Change in acceleration | Change in the amount of push/jerk |
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Average Velocity and Average Speed
Criteria | Average Velocity | Average Speed |
Definition | Change in position or displacement divided by time interval. | Total path length travelled divided by total time interval regardless of direction. |
Formula | Avg speed = Total path length/Total time interval | |
Scalar or Vector | Vector | Scalar |
Sign | Can be positive or negative | Always positive |
Unit | m/s | m/s |
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