1. The problem statement, all variables and given/known data Just before striking the ground, a 200kg mass has 400J of KE. If friction can be ignored, from what heigh was it dropped 2. Relevant equations KE = (1/2)mv^2 PEg = mgh 3. The attempt at a solution I drew a mass of 200kg and I drew the normal force at the top as well as the force of gravity (mg) at the bottom. My force of gravity = 9.81 and I know the KE = 400J I don't know what equation to use in order to find my height.