Final answer:
The concept you're referring to is called the work-energy theorem. It states that work is done when a force is exerted and there is displacement in the direction of the force.
Step-by-step explanation:
The concept you're referring to is called the work-energy theorem. It states that work is done when a force is exerted and there is displacement in the direction of the force. So, even if no work is done, it doesn't mean that no force is exerted.
For example, when you hold a load without any displacement, your muscles are still exerting a force but no work is done on the system of interest. It's important to note that work can be calculated by multiplying the force applied with the distance over which it acts.