Item EG090001: Two identical balls that are thrown up in the air will have the same amount of gravitational potential energy when they are at the same height above the ground.

A student threw two identical balls up into the air. For the balls to have the same amount of gravitational potential energy at a certain point in time, what must be true?

  1. They must be moving at the same speed.
  2. They must be at the same height above the ground.
  3. They must have been thrown at the same time.
  4. They must have been thrown with the same amount of force.