tion:The mechanical advantage of a machine is the ratio of the load (the resistance overcome by a machine) to the effort (the force applied). There is no unit for mechanical advantages since the unit for both input and output forces cancel out.One joule is defined as the amount of work done when a force of one newton is exerted through a distance of one meter. 1 joule of work = 1 N of force x 1 m of distance. In the English SYSTEM of units, where force is measured in pounds, work is measured in a unit called the foot-pound (usually abbreviated ft-lb.How They Work. As a lever, a type of simple machine, the WHEEL and axle together make work easier by requiring less energy input. They greatly reduce friction and allow for the movement of heavier loads. They also provide leverage, meaning they can multiply the force applied to them and give greater output.Energy and Work Energy is the capacity to do work or to PRODUCE heat. Internal energy is the sum of KINETIC energy and the potential energy.