Billy is sitting in a chair in class. If the action force is the downward push of his weight on the chair, what is the reaction force?

Question

A.
the upward force of the chair pushing on Billy
B.
there is no reaction force
C.
gravity
D.
the upward force of the Earth on Billy

Answer 1

The correct answer is:

A. the upward force of the chair pushing on Billy

This is an example of Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. In this case, the action force is Billy's weight acting downward on the chair, and the reaction force is the chair pushing upward against Billy.