Which type of friction occurs when an object rolls over a surface?

The correct answer is rolling friction, which occurs when an object rolls over a surface. This type of friction is distinct from other forms of friction because it involves a change in the contact point between the object and the surface, as the object turns rather than sliding or being stationary.

Rolling friction is generally less than sliding friction, making it easier for objects that roll, like wheels and balls, to move across a surface. The nature of rolling friction implies that instead of the entire surface area of the object being in contact with the surface, only a small portion comes into contact at any given moment. This minimizes resistance and allows for smoother motion.

Understanding rolling friction is essential in various applications, from vehicle design to the movement of objects in sports and everyday life, where reducing resistance helps improve efficiency and performance.