Question

A 40 N block lifted straight upward by a hand applying a force of 40 N has an initial kinetic energy of 12J. If the block is lifted 0.5 m, how mauch work does the hand do? What is the block's final kinetic energy?

Answer 1

work=force*distance

FinalKe=InitialKE+workdone-changePE
Looks like the finalKE is the same as initial KE.