velocity

go back to kinematics

=**Velocity**=


 * Velocity** is the rate of change of displacement. It requires both magnitude and and direction in order to prove it.

The rate of change of velocity is acceleration – how an object's speed or direction changes over time, and how it is changing at a particular point in time. The magnitude of velocity is speed – a quantity that is measured in meters per second (m/s or ms −1 ) when using the SI (metric) system.

Given below is a strobe picture of a ball rolling across a table. Strobe pictures reveal the position of the object at regular intervals of time; in this case, each one is 0.1 seconds.



Notice that the ball covers an equal distance between flashes. Let's assume this distance equals 20cm and display the ball's behavior on a graph plotting its x-position versus time.



Here is a fun animation describing velocity and its relation to acceleration.