contestada

8.
Billiard ball A, mass 0.17 kg, is moving due east with a velocity of 4.0
m/s. It strikes stationary billiard ball B, which has the same mass. After
the collision, ball A moves at an angle of 30° north of east with a
velocity of 3.5 m/s. Ball B moves at an angle of 60° south of east.
What is the speed of ball B?