Question

A billiard ball moving at 5 m/s strikes a stationary ball of the same mass. After the collision, the original ball moves at a velocity of 4.35 m/s at an angle of 30 o below its original motion. Find the velocity and angle of the second ball after the collision.
A) 1.25 m/s at 31.2o
B) 1.44 m/s at 60.0o
C) 2.16 m/s at 30.0o
D) 2.47 m/s at 61.9o

Answer 1

90 degrees - 30 = 60 degrees

Velocity = (5m/s - 4.35m/s x cos(30)) / cos(60)

Velocity = 2.47 m/s

The answer is D) 2.47 m/s at 61.9 degrees