Newton's third law explains that for every action force there is an equal and opposite reaction force. In the image below, the arrow represents the force of Earth pulling down on the book. This is also called the force of gravity.

Question

Based on Newton's third law and the force represented by the arrow, what is the reaction force in this scenario?
A.
The force of the book pulling down on the table.
B.
The force of the table pushing down on Earth.
C.
The force of the book pulling up on Earth.
D.
The force of the table pushing up on the book.

Answer 1

According to Newton's third law, for every action force, there is an equal and opposite reaction force. In this scenario, the action force is the force of Earth pulling down on the book (the force of gravity).

The reaction force, therefore, is the force that the book exerts upward on the Earth in response.

Given the options you provided, the correct choice is:

C. The force of the book pulling up on Earth.

This accurately reflects the reaction force to the gravitational pull of Earth on the book.