What is mechanical advantage?

Mechanical advantage is the factor by which a simple machine multiplies the input (effort) force. For example, a mechanical advantage of 4 means the machine outputs four times the force you put in. It is calculated as the output force divided by the input force (or, ideally, the distance the effort moves divided by the distance the load moves). Machines like levers, pulleys, ramps, and gears provide mechanical advantage by trading reduced force for increased distance — they do not create energy. A higher mechanical advantage means less force is needed, but over a greater distance. This concept ties together all the simple machines.