A 0.123-kg ball is dropped from a height of 1.19 m and lands on a light (approximately massless) cup mounted on top of a light, vertical spring initially at its equilibrium position. The maximum compression of the spring is to be 11.5 cm.
a) What is the required spring constant of the spring? (2mgH)/x^2
b) Suppose you ignore the change in the gravitational energy of the ball during the 11.5-cm compression. What is the percentage difference between the calculated spring constant for this case and the answer obtained in part a)?