Aball is thrown horizontally at a speed of 24 meters per second from the top of a cliff. if the ball hits the ground 4.0 seconds later, approximately how high is the cliff?

An observer that stands still as the electron moves by him, will observe

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

A2 kg ball travellng to the right with a speed of 4 m/s collidees with a 5 kg ball traveling to the left with a speed of 3 m/s. take right to be the positive direction. what is the total momentum of the two balls before they collide? what is the total momentum of the two balls after they collide?