Identical balls are dropped from the same initial height and bounce back to half the initial height. in case 1 the ball bounces off a cement floor and in case 2 the ball bounces off a piece of stretchy rubber. 1)in which case is the average force acting on the ball during the collision the biggest?

The average force acting on case 1 (cement floor) will be the greatest because of short time of contact.

The average force experienced in each case is given by Newton's second law of motion;

where;

The magnitude of the force is inversely proportional to the time of impact of the object.

In case 1:

In case 2:

Thus, the average force acting on case 1 (cement floor) will be the greatest because of short time of contact.

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