what is a variable input
Defined. Offline Version: PDF. Term variable input Definition: An input whose quantity can be changed in the time period under consideration. This should be immediately compared and contrasted with fixed input.The most common example of a variable input is labor.A variable input provides the extra inputs that a firm needs to expand short-run production. In contrast, a fixed input, like capital, provides the capacity constraint in production.his should be immediately compared and contrasted with fixed input. The most common example of a variable input is labor. A variable input provides the extra inputs that a firm needs to expand short-run production. In contrast, a fixed input, like capital, provides the capacity constraint in production.