Assignment:
Ball a, of mass m_a, is connected to ball b, of mass m_b, by a massless rod of length L. The two vertical dashed lines in the figure, one through each ball, represent two different axes of rotation, axes a and b. These axes are parallel to each other and perpendicular to the rod. The moment of inertia of the two-mass system about axis a is I_a, and the moment of inertia of the system about axis b is I_b. It is observed that the ratio of I_a to I_b is equal to 3:
{I_a}/{I_b} = 3
Assume that both balls are pointlike; that is, neither has any moment of inertia about its own center of mass.
a). Find the ratio of the masses of the two balls.
b). Find d_a, the distance from ball A to the system's center of mass.
Express your answer in terms of L, the length of the rod.
