Question

A physics book rests on a table top. A gravitational force pulls down on the book. According to Newton's third law. The force that is equal to this gravitational force is:

• A. the force the table exerts upward on the book.
• B. the force the book exerts downward on the table.
• C. the force the table exerts downward on the table.
• D. the force the book exerts upward on the table.
• E. the force the air pressure exerts down on the book.

Answer 1

The correct option is A the force the table exerts upward on the book.

Sir Newton's third law of motion states that for an action there is always an equal and opposite reaction . These two forces always act on different objects . When a book is kept on a table , weight (gravitational force) of book acts on table vertically downwards and as a reaction of weight , table also exerts an equal and opposite ( upward) force on book .