Question

9
which explanation describes the forces involved for a person to walk down the sidewalk?
a. the person’s feet push backward on the sidewalk; the sidewalk pushes forward on the person
b. the person’s feet push forward on the sidewalk; the sidewalk does not push on the person
c. the person’s feet push forward on the sidewalk; the sidewalk pushes forward on the person
d. the person’s feet push backward on the sidewalk; the sidewalk pushes backward on the person

Explanation:

This follows Newton's Third Law of Motion, which states that for every action, there is an equal and opposite reaction. When walking, the backward push of the feet on the sidewalk (action) creates a forward push of the sidewalk on the feet (reaction), which propels the person forward.

Answer:

A. The person's feet push backward on the sidewalk; the sidewalk pushes forward on the person.