Question

Are there limitations to Newton’s third law? Why?

Answer 1

In order to understand the limitations of Newton’s third law, first we need to understand the basic concept of Newton’s third law of motion. The definition of Newton's third law of motion states that every action has an equal and opposite reaction.

Complete answer:
Yes, there are limitations in Newton’s third law of motion. Newton’s third law of motion states that the forces exerted by two interacting bodies on each other are equal and opposite. But this has a condition. The condition is that the forces should be measured simultaneously. But, the simultaneous measurement of the two forces is only possible for ordinary practical purposes. This means that the law ceases to hold good for particles of atomic dimensions, for which simultaneous measurement of the forces is almost impossible.

Thus, we can say that the limitation of Newton's third law of motion is that it holds good for practical purposes but fails when it is applied at the atomic level.

Additional information: The best example to explain Newton’s third law of motion is the walking of a man on the ground. When a man walks on the ground, then the man exerts a force in the backward direction. This force applied by the man is known as action. As a result of this force applied by the man, an equal and opposite force is applied by the ground on the man and this force helps the man to walk in the forward direction. This force is called the reaction.

Note: We know that according to Newton’s third law of motion, every acting has an equal and opposite reaction. In some of the cases, direction as well as the magnitude is decided by one body between these two. Whereas in some cases, both bodies together determine direction as well as the magnitude.