A Pair of Identical Balls Are Connected by a Massless

Multiple Choice

A pair of identical balls are connected by a massless rod, and thrown straight up into the air. The velocity of the center of mass is initially 17.2 m/s upward. Precisely 1.0 s later, one of the balls is measured to be instantaneously at rest. What is the velocity of the other ball at this time? Ignore air resistance.

A) 14.8 m/s up
B) 9.8 m/s down
C) 7.4 m/s up
D) 7.4 m/s down