A 0.311 kg tennis racket moving 30.3 m/s east makes an elastic
collision with a 0.0570 kg ball
moving 19.2 m/s east. Find the
velocity of the tennis ball after the
collision.
(Unit = m/s)

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final

An athlete is holding 24 lb of weights at a height of 6 inches above the stack as shown. to lower the weights, she applies a constant force of 5 lb to the handle. determine the velocity of the weights immediately before they hit the stack.

By what primary heat transfer mechanism does the sun warm the earth?