Question

A ball is thrown into the air with 100 J of kinetic energy, which is transformed to gravitational potential energy
at the top of its trajectory. If it returns to its original level less than 100 J of kinetic energy, the ball
encountered
a. air resistance.
b. gravitational acceleration.
c. a faster descent time.
d. a decrease of its mass.

Answer 1

Answer:

Air resistance

Explanation:

Despite the law of conservation of energy stating that energy can neither be created nor destroyed but can only be transformed from one state to another, some energy is usually lost in the process of transformation and its majorly attributed to frictional loss. Friction opposes normal movement hence in air, air resistance tends to reduce the original energy compared to the initial. That is why the final energy in this case is slightly less than the original energy.