Okay, so we did a lab where we dropped a bouncy ball (mass = 56.4 g) from 1meter above the ground, and measured the height that it bounced up to. We need to calculate the: a) loss of energy due to the first bounce for each of the balls b) the speed with which the ball strikes the floor c) how many bounces would it take before the ball has lost all of its energy The speed with which the ball strikes the floor with. Just set a = -9.8 m/s^2, and have vi = 0, so vf^2 = vi^2 + 2ad, so you get vf to be sqrt of 19.6 m/s, so ~4.427 m/s, ok, so did I do that part right? Now for energy lost, do I use the Ke1 + Pe1 = Ke2 + Pe2? I'm kind of confused, and as for how many bounces, what equation do I use? Thanks a lot in advance.