What term describes the effort applied to move a load in a mechanical system?

The term that describes the effort applied to move a load in a mechanical system is "Force." In physics, force is defined as any interaction that, when unopposed, will change the motion of an object. This includes the application of physical effort to lift, pull, or push an object.

In the context of mechanical systems, force can be exerted through various means, such as muscle power in manual systems or through machinery in powered systems. It is essential in determining how much load can be moved or how efficiently a system operates.

Other terms in the options, such as "Load," refer to the weight or resistance that the force acts upon, while "Output Work" and "Input Work" relate to the energy transferred through the system during work performed. However, neither of these terms directly conveys the concept of effort being applied, making "Force" the most accurate description in this scenario.