Why does a wheel reduce friction compared to other methods?

A wheel reduces friction compared to other methods primarily because rolling friction is less than sliding friction. When an object rolls, like a wheel, it experiences a type of friction that primarily involves the deformation of the contact surface rather than the sliding of two surfaces against each other.

In rolling, the point of contact does not remain in contact as it would in sliding; instead, it continuously lifts off and new points of contact are made. This results in less surface area in contact at any moment, thus reducing the energy lost to friction. Additionally, rolling typically involves much smaller resisting forces, making movement more efficient.

This principle is foundational in various applications, from vehicles to machinery, where reducing friction can lead to significant improvements in efficiency and performance.