1. Why We Reduce Friction
Friction is helpful in many situations, but in machines and vehicles it can cause problems like wear, heat, and energy loss. To save energy and improve efficiency, we often need to reduce unwanted friction.
There are several simple methods used in daily life, industries, and transportation systems to reduce friction.
2. Lubrication
Lubrication is one of the most common methods to reduce friction. A thin layer of oil, grease, or any suitable lubricant is applied between two surfaces.
2.1. How Lubrication Works
Lubricants fill the tiny irregularities on surfaces, making them smooth. This reduces interlocking and allows objects to move more easily.
2.2. Examples
- Applying oil to bicycle chains.
- Greasing machine parts.
- Using engine oil in cars.
3. Using Ball Bearings
Ball bearings reduce friction between rotating parts by replacing sliding friction with rolling friction, which is much smaller.
3.1. How Ball Bearings Work
Small metal balls roll between the moving surfaces, reducing resistance. This makes the movement smoother and requires less force.
3.2. Where Ball Bearings Are Used
- In bicycle wheels.
- In electric motors.
- In fans and skates.
4. Streamlining
Streamlining is shaping objects so air or water can flow smoothly around them. This reduces fluid friction (air resistance or water resistance).
4.1. Streamlined Shapes
Streamlined shapes have pointed fronts and narrow backs. This helps reduce drag and allows smooth movement.
4.2. Examples
- Airplanes have streamlined bodies.
- Cars and trains are designed to reduce air resistance.
- Fish and birds have natural streamlined shapes.
5. Making Surfaces Smooth
Smoother surfaces have fewer bumps and irregularities, reducing friction. Polishing reduces roughness and makes movement easier.
5.1. Examples
- Polished wooden floors allow easy sliding.
- Machine parts are smoothed to reduce wear.
- Slides in playgrounds are polished for smoother movement.
6. Using Special Materials
Certain materials like Teflon and graphite naturally reduce friction. They are used where smooth and low-resistance surfaces are important.
6.1. Examples
- Non-stick cookware uses Teflon.
- Graphite powder is used in locks.
- Special low-friction coatings in machines.
7. Reducing Friction Where Needed
Not all friction is bad. We reduce friction only when it causes energy loss or wear. In other situations like walking or driving, friction must be increased.
7.1. Examples of Reducing vs Increasing Friction
- Reduce friction: inside engines, machines, wheels.
- Increase friction: tyre treads, shoe soles, sand on slippery surfaces.