1. There is a spring connected to a mass on a frictionless horizontal surface. Another mass smaller in size is placed ontop of the bigger mass. It asks find the amplitude so that the smaller mass falls off. Coeffient of friction is 0.4 between the two masses. K is given as 200 N/m 2. Simple harmonic motion eqn's 3. F = kx friction force between the smaller mass and bigger mass is = mu * Normal Normal = smaller mass times 9.81 m/s^2 so i got my frictional force... is that equal to Kx where K is given so i solve for x?