Question

question 4 (1 point)
a ball drops some distance and gains 30 j of kinetic energy. do not ignore air resistance. how much gravitational potential energy did the ball lose?
more than 30 j
exactly 30 j
less than 30 j
cannot be determined from the information given

Explanation:

When a ball drops with air resistance, the gravitational potential energy (GPE) it loses is converted into kinetic energy (KE) and work done against air resistance (which becomes thermal energy, etc.). So the loss in GPE = gain in KE + energy lost to air resistance. Since the ball gains 30 J of KE, the loss in GPE must be more than 30 J (because some energy is used to overcome air resistance).

Answer:

A. more than 30 J