Question

1. which pair of forces is not an action - reaction force?

a toddler pushes on a toy, and the toy pushes back on the toddler
a person pushes on a wall, and the wall pushes back on the person
a dog pulls on a rope toy, and the owner pulls on the other side
a volleyball player hits a volleyball, and the volleyball hits the player

Explanation:

According to Newton's third law, action - reaction forces act on two interacting objects. In option C, the dog and the owner are two separate entities pulling on the same rope toy. The forces here are not an action - reaction pair in the sense of Newton's third law (where one object exerts a force on another and that second object exerts an equal and opposite force back on the first). In options A, B, and D, there are two objects (toddler - toy, person - wall, player - volleyball) where each exerts a force on the other and vice - versa, which is characteristic of action - reaction force pairs.

Answer:

C. a dog pulls on a rope toy, and the owner pulls on the other side