Question

A circus performer juggles 4 identical balls. The performer throws each ball upward with the same initial velocity and releases each ball at the same height. The ball with the greatest kinetic energy will be the ball that the juggler

a) throws upward, just after it leaves her hand
b) is watching, just as it reaches its highest point
c) is about to catch, just before it lands in her hand
d) does not catch, just before it lands on the floor

Answer 1

The ball thrown by the juggler has the greatest kinetic energy just after it leaves the juggler's hand, as energy transitions from kinetic to potential during its rise.

Step-by-step explanation:

The ball with the greatest kinetic energy will be the ball that the juggler throws upward, just after it leaves her hand. At this point, all the energy that was applied to the ball is kinetic because it has not yet been converted to potential energy. As the ball rises, kinetic energy is converted to gravitational potential energy, which reaches a maximum at the ball's highest point where kinetic energy is zero. Consequently, when the ball is about to be caught or hits the floor, it has lost some energy to air resistance and possibly deformation if it bounces, resulting in lower kinetic energy than at the throw.

The ball with the greatest kinetic energy will be the ball that the juggler throws upward, just after it leaves her hand.