1. The problem statement, all variables and given/known data A gymnast of mass 40kg is practising on a trampoline. The gymnast lands with a speed of 6.3m/s. The gymnast rebounds with a speed of 5.7m/s. a) Calculate the change in momentum of the gymnast b) The gymnast was in contact with the trampoline for 0.50s. Calculate the average force exerted by the trampoline on the gymnast. 2. Relevant equations Momentum = mass x velocity Force = change in momentum/time 3. The attempt at a solution a) momentum before = 40kg x 6.3m/s = 252kgm/s momentum after = 40kg x (-5.7m/s) = -228kgm/s change im momentum = final momentum - initial momentum = -228kgm/s - 252kgm/s = -480kgm/s b) Force = -480 / 0.50s = -960N. Is this correct?