A pan of mass 2 kg is resting in equilibrium on a spring of stiffness 200 N/m, as shown. A 0.5 kg lump of clay is released 5 m above the pan so that it hits the pan with some velocity and sticks to it. What will be the maximum downward descent of the pan from its initial position?

[Hint : Conserve momentum of clay + pan during collision and then apply energy equation. Do not neglect the initial compression of the spring]