Question

A ball is dropped on the floor from a height of 10 m .It rebounds to a height of 2.5 m .If the ball is the contact with the floor for 0.01 seconds,then the average acceleration during contact is nearly how much.

Answer 1

Why is this in the history section? Anyways on contact it has velocity +98 m/s (+ denotes downwards), after rebound it reaches a height of 2.5 m , so it must have a velocity -7 m/s. So total change in velocity on contact over total time would give avg. acceleration.