15. We take the reference point for gravitational potential energy at the position of the marble when the spring is compressed. (a) The gravitational potential energy when the marble is at the top of its motion is gUmgh=, where h= 20 m is the height of the highest point. Thus, Ug=×=−50 109809832....kgm s20 mJchdibg(b) Since the kinetic energy is zero at the release point and at the highest point, then conservation of mechanical energy implies ΔUg+ ΔUs= 0, where ΔUsis the change in
This is the end of the preview. Sign up
access the rest of the document.