To reduce friction following methods are commonly used:
- Polishing: If we polish a surface, it becomes smooth and friction is reduced. Through polishing, unevenness of the surfaces is reduced.
- Lubricating: By applying lubricants (like oil) to surfaces, friction is reduced. When we apply lubricant to surfaces, a thin layer of lubricant is formed over there and moving surfaces do not directly rub against each other.
- Using ball bearings: This way of reducing friction involves the principle that an object is rolled instead of sliding. The use of ball bearing converts sliding friction into rolling friction.
- Separation of surfaces by air: Another way of reducing friction is to separate the surfaces by air. This is how, a hovercraft works. A hovercraft moves on a layer of air between its hull and the water. The layer of air reduces friction allowing the hovercraft to move easily.
- Giving a streamlined shape: Boats, cars, planes and rockets are streamlined to reduce friction with water or air.
