The change in velocity of a moving body over a unit of time is called acceleration.

Here's a breakdown:

* Velocity: Measures both the speed and direction of an object.

* Change in Velocity: Means the object is either speeding up, slowing down, or changing direction.

* Unit of Time: Could be seconds, minutes, hours, etc.

Formula for Acceleration:

Acceleration (a) = (Final Velocity (v) - Initial Velocity (u)) / Time (t)

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