Assume that h takes the value found in the previous question, and that the collision between the two masses is perfectly elastic. For what value of \Delta x will m rebound to a maximum height that is exactly equal to its original height?
Answer Choices
A. \frac{\pi g}{2 k} \sqrt{\frac{m^{3}}{M}}
B. \frac{\pi g}{k} \sqrt{\frac{m^{3}}{2 M}}
C. \frac{2 g}{\pi k} \sqrt{\frac{2 m^{3}}{M}}
D. \frac{4 m g}{\pi k}
E. \frac{\pi m g}{2 k}