Explain when we have to reduce …

• Increasing and Reducing Friction:

Friction can be increased by the following methods:

1. Grooves are made in the soles of shoes to increase friction and prevent slipping.
2. Treads are made in the tyres of vehicles to increase friction and prevent skidding of vehicles on wet roads.
3. Spikes are provided in the shoes of players and athletes to increase friction and prevent slipping.
4. Gymnasts apply some coarse substance on their hands to increase friction for better grip.
5. Machine belts are made of special materials to increase friction and drive machine wheels properly.

Methods of reducing friction:

1. Friction can be reduced by making the surfaces smooth by polishing.
2. Friction can be reduced by applying lubricants like oil or grease to the rubbing surfaces.
3. Friction can be reduced by using wheels to move objects.
4. Friction can be reduced by using by using ball bearings between the moving parts of machines.