1. The problem statement, all variables and given/known data An 80 kg man jumps from a height of 2m onto platform mounted on springs. As the springs compress the platform is pushed down a maximum distance of 0.2m below its initial position, and it rebounds. a) What is the man's speed at the instant the platform depressed 0.1m? b) If the man had just stepped gently onto the platform how much would it have been pushed down? 2. Relevant equations 3. The attempt at a solution A) I am stuck. I think maybe Ua + Ka = Ub + Kb and mgh = 1/2kmv2 but then I don't know how to get k and v. B) ΣFy = 0 ΣFy = Fs - mg Fs = kd 0 = kd - mg kd = mg Now what?