The force to be overcome by a simple machine is called the load.

Here's why:

* Load: This refers to the weight or resistance that the machine is designed to move or overcome. It's the force the machine needs to work against.

* Effort: This is the force applied by the user to operate the machine.

* Mechanical Advantage: This is the ratio of the load to the effort. A higher mechanical advantage means the machine multiplies the effort force to overcome a larger load.

So, when you use a simple machine like a lever to lift a heavy object, the object itself is the load, and the force you apply to the lever is the effort.