Question

What is the need in the magnitude and line of action in newton's third law of motion?

Answer 1

NEWTON'S THIRD LAW: NEWTON'S THIRD LAW OF MOTION states that for EVERY ACTION, there is an EQUAL and OPPOSITE REACTION. The FORCES of an ACTION and REACTION between bodies in contact have the samemagnitude, same line of action, and opposite sense, or in other terms, they are equal, opposite, and collinear.
Hope it's help you