Friction can be both useful and harmful.
So in daily life, we sometimes increase friction and sometimes reduce friction, depending on the need.

How to Increase Friction

We increase friction when we need more grip or control.

1. Making surfaces rough

  • Rough surfaces have more irregularities.

  • Example: Sand spread on icy roads for better grip.

2. Using treaded tyres and shoes

  • Tyres and sports shoes have grooves to prevent slipping.

  • More friction → better control.

3. Using rough materials for grip

  • Hand grips, brake pads, and carpets use rough surfaces.

B. How to Reduce Friction

We reduce friction when we want smooth and easy movement.

1. Using lubricants (oil, grease, powder)

  • Lubricants fill the gaps between surfaces and reduce friction.

  • Used in machines, bicycle chains, motors.

2. Polishing surfaces

  • Makes surfaces smooth → reduces irregularities → lowers friction.

3. Using wheels or rollers

  • Rolling friction is much less than sliding friction.

  • That’s why heavy objects are placed on rollers to move them easily.

4. Making objects streamlined

  • Streamlined shapes reduce friction in air and water.

Wheel and Ball Bearings

Wheels and ball bearings are special tools used to reduce friction and make movement smoother.

1. Why Wheels Reduce Friction

  • Without wheels, objects must slide, which produces a lot of friction.

  • With wheels, objects roll, and rolling friction is much less than sliding friction.

Result:
Movement becomes easier and requires less force.

Example:

  • Suitcases with wheels

  • Cars, bicycles, trolleys

2. What Are Ball Bearings?

Ball bearings are small metal balls placed between moving parts of a machine.

How they work:

  • The balls roll instead of slide.

  • This changes sliding friction into rolling friction, which is much less.

Where they are used:

  • Cycle wheels

  • Skateboards

  • Fans

  • Motors

  • Car engines

3. Why Ball Bearings Are Important

  • Reduce friction

  • Reduce heat

  • Prevent wear and tear

  • Make machines work smoothly

  • Increase the life of machines

 

PreviousNext