Calculating the Net Force of a Bouncing Ball

AI Thread Summary
The discussion focuses on calculating the average net force acting on a rubber ball during its contact with the floor after bouncing. The ball has a mass of 0.08 kg, strikes the floor at 10 m/s, and rebounds at 8 m/s, with a contact time of 0.05 seconds. Initial calculations using kinetic energy yielded a force of 80 N, which seemed excessive. The correct approach involves calculating the change in momentum, resulting in a force of 28.8 N, which is deemed more reasonable. The conversation emphasizes the importance of using the correct formula for average force in such scenarios.
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Homework Statement



a rubber ball mass of 0.08 kg bounces vertically on a concrete floor. the ball strikes the floor at 10 ms-1 and rebounds at 8 ms-1. The time in contact with the floor is 0.05 sec.
Calculate the average net force acting on the ball during the contact with the floor.

Homework Equations


E=F/t

F=0.5mv^2

The Attempt at a Solution



(0.5x0.08x10^2)/0.05
= 80N

I get a force of 80 N but to me it seems to much to be true... Help?
 
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You have to find the average force which is found by
F= (change in momentum)/time.
 
rl.bhat said:
You have to find the average force which is found by
F= (change in momentum)/time.

So change in momentum= 1.44 kgms-1

F=1.44/0.05
=28.8N

that seems more plausible Thanks for the help!
 
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