1. The problem statement, all variables and given/known data A 65 kg man jumps at a velocity of 1.8 m/s. The contact time is 0.45 seconds. Find the average force exerted by the man. 2. Relevant equations F=ma+mg 3. The attempt at a solution F=65*(1.8/.45)+65*9.81 I'm not sure if the equation has to be divided by the contact time, .45 seconds, to obtain the average force acting on the man.