Answer: (b) always act on different bodies in opposite directions
Newton’s third law of motion states that when one body exerts a force on the other body, the first body experiences a force that is equal in magnitude in the opposite direction of the force which is exerted.
let us consider a book resting on a table. The book applies a downward force equal to its weight on the table.
- According to the third law of motion, the table applies an equal and opposite force to the book.
- This force occurs because the book slightly deforms the table, as a result, the table pushes back on the book like a coiled spring.
- Newton’s third law of motion implies the conservation of momentum.