The students measure the mass of the contraption and the attached masses and determine that the value of m is so much greater than the mass of the contraption that the mass and rotational inertia of the contraption itself can be ignored. The students then perform several trials in which the distance r at which the masses are attached is increased with each trial, and the time t required for the object to fall at a constant distance D is measured. Should the students expect the value of t to increase, decrease or remain the same as the value of r increases? Explain your reasoning qualitatively using principals relating to forces and Newton's Second Law? Explain your reasoning qualitatively using principles related to energy conservation?