Methods of reducing friction:

1. The friction can be reduced by making the sliding surfaces smooth.
2. The friction can be reduced by making the fast-moving objects streamlined. shape (fish shape) such as cars, airplanes, etc. this causes the smooth flow of air and thus minimizes air resistance at high speeds.
3. The friction can be reduced by using ball bearings or roller bearings because the rolling friction is lesser than the sliding friction.
4. The friction can be reduced by lubricating the sliding surfaces.

DO YOU KNOW

Friction is highly desirable when climbing up a hill.