1. The problem statement, all variables and given/known data A 4.20 kg block is set into motion up an inclined plane with an initial speed of v0 = 7.70 m/s (Fig. P7.25). The block comes to rest after traveling 3.00 m along the plane, which is inclined at an angle of 30.0° to the horizontal. 1. For this motion, determine the change in the block's kinetic energy. DeltaK = 1/2m(vf^2-vi^2)^2=-1/2mvi^2= -124.5J This next question is the portion I am having problems with: 2. For this motion, determine the change in potential energy of the block-Earth system. 2. Relevant equations DeltaU = mg(3.00)sin30.0 3. The attempt at a solution =(4.20)(9.8)(3.00)(0.454) =56.1 So what is wrong with my answer??