1. The problem statement, all variables and given/known data A ball of mass m falls from height hi to height hf near the surface of the Earth. When the ball passes hf, it has a speed of vf. Ignore air resistance. Consider the system T which consists of the ball only. Write an expression for each of the following quantities in terms of the given variables and any physical constants: The net work on system T The change in kinetic energy of system T The change in potential energy of system T 2. Relevant equations ΔKE = 1/2mv2 ΔPE = -mgh = -mg(hf - hi) Wnet ext = ΔKE 3. The attempt at a solution I know that the total energy throughout the system does not change. However, Potential Energy caused by gravity does change into Kinetic Energy as the ball falls for the initial height. Therefore I believe that the net work on system T is ΔKE = 1/2mvf2. The change in kinetic energy is ΔKE = 1/2mvf2 And the change in Potential energy is 0. This is where I felt that I may be completely wrong since the net work is all the forces multiplied by displacement I think my net work formula or "expression" is incorrect. Could anyone help me verify my mistake? Thanks!!!