A conservative force of 5 N causes a body to move 2 m in the direction of the force. The change of the body’s potential energy associated with the force is: (a) zero, (b) +10 J, (c) -10 J, (d) infinite. Let's say the force is pushing the body for 2m, there must be a change in KE. But, for change of KE, there must be change in PE. I don't understand this. Can you explain to me how W=DKE=DPE?