"Exert force" is a common phrase used to describe the act of applying a force.

Force is a push or pull that can cause a change in the motion of an object.

Here's what the phrase means:

* Exert: To apply, use, or put forth effort.

* Force: A push or pull.

Therefore, "exert force" means to apply a push or pull on something.

Here are some examples of exerting force:

* Pushing a door open

* Lifting a heavy box

* Throwing a ball

* Pulling a wagon

The amount of force you exert can affect the outcome of the action. For example, you need to exert more force to push a heavy door open than a light door.

Let me know if you have any other questions!