If body A exerts a force on body B, then body B exerts an equal and opposite force on body A. This is known as Newton's Third Law of Motion.

Here's a breakdown:

* Equal: The magnitude of the force exerted by B on A is the same as the magnitude of the force exerted by A on B.

* Opposite: The direction of the force exerted by B on A is opposite to the direction of the force exerted by A on B.

Example:

Imagine you push a wall (body A). You exert a force on the wall. The wall, in turn, exerts an equal and opposite force on you. You feel this force as resistance.

Key Points:

* These forces always occur in pairs. There is no force without an equal and opposite reaction.

* The forces act on different objects. One force acts on body A, while the other acts on body B.

* The forces are simultaneous. They occur at the same time.

Let me know if you have any other questions!