500
This is what will happen when two balls of different masses (like a golf ball and a ping pong ball) hit each other. (Consider all of Newton's 3 laws)
What is...when the ping pong hits the golf ball, the golf ball hits the ping pong ball with the same amount of force in the opposite direction? (3rd law). What is...the ping pong ball will accelerate more because it has less mass (2nd law). What is...the balls will eventually come to a stop because friction acts as an unbalanced force, so the objects will slow down (2nd law). If there was no friction, the balls would continue to move apart at a constant speed (1st law)