A ball of mass 500g is dropped from rest 2m above the ground. When it reaches the ground it is travelling at 5m/s. How much energy has been dissipated?
Initial energy (Gravitational Potential): E = mgh = 0.5 x 9.81 x 2 = 9.81J Final energy (Kinetic): E = mv2/2 = (0.5 x 52)/2 = 6.25J Energy lost = 9.81 - 6.25 = 3.56J
