A disc of mass 3m and a disc of mass m are connected by a massless spring of stiffness k. The heavier disc is placed on the ground with the spring vertical and the lighter disc on top. From its equilibrium position, the upper disc is pushed down by a distance δ and released. Then:
(1) If δ>k3mg, the lower disc will bounce up.
(2) If δ=k2mg, the maximum normal reaction from the ground on the lower disc is 6mg.
(3) If δ=k2mg, the maximum normal reaction from the ground on the lower disc is 4mg.
(4) If δ>k4mg, the lower disc will bounce up.