Question

Choose the correct statement from the following:

1. Grease is used to reduce friction in the bicycle chain.
2. Ball bearings are used to reduce friction in a fan.
3. Oil is used to increase friction in car parts.
4. Talcum powder is used to reduce friction on a carrom board.

• A.
  2, 3 and 4
• B.
  1, 2 and 4
• C.
  1, 3 and 4
• D. 1, 2, 3 and 4

Answer 1

The correct option is B

1, 2 and 4
The following methods can be used to reduce friction between the surfaces:

1. Lubrication ( Greasing or oiling of machine parts)
2. Ball bearings (Rotating parts of fan or using talcum powder on a carrom board)
3. Streamlined Shape (Used in designing the shape of high speed vehicles)

Therefore, statements 1, 2 and 4 are correct.