Find k for the spring from the forces when the frame hangs at rest, use constant acceleration equations to find the speed of the putty just before it strikes the frame, apply conservation of momentum to the collision
between the putty and the frame and then apply conservation of energy to the motion of the frame after the collision.
SET UP: Use the free-body diagram for the frame when it hangs at rest on the end of the spring to find the force
constant k of the spring. Let s be the amount the spring is stretched.