4. Two tennis balls roll towards each other with the same mass, 0.23 kg. Tennis *
ball C has a forward velocity of 2.8 m/s and tennis ball D has a velocity of 4.5 m/s
in the opposite direction. After they collide, tennis ball C has a velocity of 3.2 m/s
in the direction it came from. How fast was tennis ball D moving after the
collision?
Your answer
