posted by kabo on .
A pitcher throws a 0.140-kg baseball, and it approaches the bat at a speed of 40.0m/s. The bat does nonconservative W=70.0J on the ball in hitting it. Ignoring air resistance, determine the speed of the ball after the ball leaves the bat and is 25.0m above the point of impact.
Please give me some hints to do it!!THANKS THANKS THANKS!!!
There seems to be some information missing here. If the impact is NONconservative, one needs to know how much of the batter's work is converted to kinetic energy of the ball. One also needs to know what fraction of the ball's initial kinetic energy is retained after it bounces off the bat.
Lacking further information, I see no choice but o assume that the impact IS conservative, and add the batter's work to the intial kinetic energy of the ball to get the KE after it leaves the bat.
Once you have the speed that it leaves the bat, subtract the potential energy change from the initial kinetic energy to get the kinetic energy (and from that, the velocity0 at an altitude of 25 m.