Question

A billiard ball strikes and rebounds from the cushion of a pool table perpendicularly. the mass of the ball is 0.38 kg. the ball approaches the cushion with a velocity of +2.50 m/s and rebounds with a velocity of -1.90 m/s. the ball remains in contact with the cushion for a time of 3.40 × 10-3 s. what is the average net force (magnitude and direction) exerted on the ball by the cushion? f = entry field with correct answer entry field with incorrect answer entry field with correct answer

Answer 1

In physics, the quantity that describes the momentum and the time the two objects collided is the impact force. This is the net force applied by the two objects as one system during collision at a very short interval of time. It is denoted as variable J with the equation:

J = 2mv/t, where m is the mass, v is the velocity on impact and t is the time of collision when the two objects stick together. Substituting the values,

J=(2*0.38 kg*+2.5 m/s)/0.0034 s
J = 558.8 Newtons

Therefore, the force during that short time that the ball and cushion were in contact is equal to 558.8 Newtons.