On a horizontal surface, a crate with mass 50.0 kg is placed against a spring that stores 360 J of energy. The spring is released, and the crate slides 5.60 m before coming to rest. What is the speed of the crate when it is 2.00 m from its initial position?

Solution 44P Step 1: Maximum energy of the crate will be, PE = 360 J when it is compressed. Therefore, the maximum energy is nothing but the work done on the spring. So we can write, W = 360 J We know that, W = FS The distance it moved, S = 5.60 m Then F = W/S = 360 J/5.60 J = 64.28 N