A wheel and axle is a simple machine that consists of a wheel attached to a shaft, or axle. The wheel and axle can be used to lift heavy objects by wrapping a rope or chain around the wheel and axle. As the wheel is turned, the rope or chain will lift the object.

The wheel and axle is a mechanical advantage, which means that it makes it easier to lift heavy objects. The mechanical advantage of a wheel and axle is determined by the ratio of the radius of the wheel to the radius of the axle. The larger the ratio, the greater the mechanical advantage.

Wheel and axles are used in a variety of applications, including cars, bicycles, and cranes.