Question

is acceleration the measure of time taken for velocity change or the number of times velocity changes for a given time????????????...plzzzz quick!!!!!!

Answer 1

It is neither. Acceleration is defined as the rate of change of velocity, i.e.
if the velocity of a moving body changes with time, then average acceleration of that body can be given by (total change of velocity during the motion) / (total time taken during that motion). However, such a definition doesn't provide a detailed description of a body's motion i.e. how it's velocity changed at different rates during different times throughout the motion. And in order to solve this crisis, the instanteous definition of acceleration is applied which is basically the derivative of the velocity function with respect to time.