Two pendulum bobs of unequal mass are suspended from the same fixed point by strings of equal length.The lighter bob is drawn aside and then released so that it collides with the other bob on reaching the vertical position.The collision is elastic.What quantities are conserved in the collision?
A)Both kinetic energy and angular momentum of the system
B)Only kinetic energy
C)Only angular momentum
D)Angular speed of lighter bob
E)None of the above

Question

Quizplus · Accepted Answer

In an elastic collision, both kinetic energy and angular momentum are conserved. This is because elastic collisions conserve kinetic energy by definition, and angular momentum is conserved in any collision (or interaction) that has no external torques acting on the system.

Two Pendulum Bobs of Unequal Mass Are Suspended from the Same