A 40.8 g ball of clay hits and sticks to a 3.41 kg block sitting at rest on a frictionless surface. What is the speed of the block after the collision if the initial speed of the ball of clay is 5.04 m/s?
b)What percentage of the system's initial energy is lost?
The Attempt at a Solution
for the first part i figured out the speed final which is 0.0596 m/s
for the second part for each i figured the initial energy and then the final energy using the energy equation for both objects involved. after this part i am stuck to figure out the energy lost i came up with this equation 100-(Einitial-Efinal/Efinal) x100.. i used it and am not getting the right answer..pls. help