A wheel and axle is a disk and cylinder joined together. These two objects are only a simple machine when used in tandem. A wheel and axle is a modified first-class lever. When force is applied to the axle, the force is multiplied and transferred to the wheel. This causes the wheel to cover more area. Readers will learn about the invention of the wheel and axle, where wheels and axles can be found, and how they make difficult jobs easier.
