A pair of identical balls are connected by a massless rod and thrown straight up into the air, such that the center of mass of the pair reaches a maximum height of 13.2 m above the point of release. On the way up, when the center of mass is at 6.6 m above to point of release, the velocity of one ball is measured to be 7.7 m/s straight downward. What is the velocity of the other ball at this time? Ignore air resistance.
A) 30.2 m/s up
B) 23.8 m/s up
C) 19.1 m/s up
D) 15.7 m/s up
E) 3.7 m/s up

Question

Quizplus · Accepted Answer

Explanation:The total momentum of the system is zero, so the momentum of the two balls must be equal in magnitude but opposite in direction. Therefore, the velocity of the other ball is 30.2 m/s up.

A Pair of Identical Balls Are Connected by a Massless