Question

a crane drops a .3 kg steel ball onto a steel plate. the ball's speeds just before impact and after are 4.5 m/s and 4.2 m/s respectively. If the ball is in contact with the plate for .03 s, what is the magnitude of the average force that the ball exerts on the plate during impact?

Answer 1

Presumably the steel ball bounced and changed directions. The momentum change is therefore 0.3 kg*(4.5 + 4.2 kg.s) = 2.61 kg m/s

Set that equal to the impulse (Force * time) and divide by the time interval to get the average force.

Answer 2

87 N

Answer 3

87