Newton's Third Law of Motion (no examples)

Every force is part of an interaction between one thing and another. These forces are equal in magnitude and opposite in direction, and they constitute a single interaction.

An interaction requires a pair of forces acting on two separate objects. Which exerts force and which receives the force? Isaac Newton’s response was that neither force has to be identified as “exerter” or “receiver”; he concluded that both objects must be treated equally.

Newton’s third law states: Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first. We call one force the action force and the other the reaction force, but it doesn’t matter which one we call action force and which one we call reaction force. The important thing is that they are co-parts of a single interaction and that neither force exists without the other.

Since action and reaction force are equal and opposite to each other, why don’t they cancel to zero? You can’t cancel a force on one system with a force on another system. In this case, action and reaction forces don’t cancel.

A falling object pulls upward on Earth with as much force as Earth pulls downward on the object. The resulting acceleration of the falling object is evident, while the upward acceleration of Earth is too small to detect.

Forces are interactions between different things. Every contact requires at least a twoness; there is no way that an object can exert a force on nothing. Forces, whether large shoves or light nudges, always occur in pairs, each of which is opposite to the other. Thus, we cannot touch without being touched.

Just as a pair of vectors at right angles can be combined into one resultant vector, any vector can be resolved into two component vectors perpendicular to each other. These two vectors are known as the components of the given vector they replace. The process of determining the components of a vector is called resolution. Any vector drawn on a piece of paper can be resolved into a vertical and horizontal component.

Newton’s third law, the law of action-reaction: Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first. Forces occur in pairs, one action and the other reaction, which together constitute the interaction between one object and the other. Action and reaction always occur simultaneously and act on different objects. Neither force exists without the other.