Question

as an apple falls from a tree, which types of energy are changing?

a. gravitational potential energy and kinetic energy
b. light energy and gravitational potential energy
c. kinetic energy and nuclear energy
d. elastic energy and sound energy

Explanation:

When an apple falls from a tree, its height decreases. Gravitational potential energy ($U = mgh$, where $m$ is mass, $g$ is acceleration due to gravity, and $h$ is height) depends on height. As $h$ decreases, gravitational potential energy decreases. At the same time, the apple's speed ($v$) increases. Kinetic energy ($K=\frac{1}{2}mv^{2}$) depends on speed. As $v$ increases, kinetic energy increases. There is no mention of light energy (related to electromagnetic radiation), nuclear energy (related to atomic nuclei), elastic energy (related to deformation of elastic objects), or sound energy (related to sound waves) in the context of a falling apple.

Answer:

A. Gravitational potential energy and kinetic energy