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What is gained and lost when a machine increases force?

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A diagram displays six types of simple machines with labeled illustrations: inclined plane, wedge, screw, lever, wheel and axle, and pulley, each shown with real-world examples like ramps, axes, screws, seesaws, door handles, and pulleys lifting objects. — simple machine Six simple machines for transforming energy into work.

In the operation of a simple machine, forces and motions are inseparable and exist in an inverse ratio. When a machine is used to increase force—a function known as mechanical advantage—there is a corresponding trade-off in motion.12

Specifically, what is gained in force is lost in motion (displacement or velocity). For example, if a lever is used to produce an output force that is 10 times greater than the input force, the input motion must be 10 times greater than the output motion. This principle ensures that the work input remains balanced with the work output, accounting for the fact that work is defined as the product of force and distance. In practical applications, friction further ensures that the actual work output is always less than the work input, meaning machines are never 100 percent efficient.123