Quiz on Friction

What is friction?

• A force that pushes objects

• A force that opposes motion

• A force that increases motion

• None of the above

Which of the following surfaces will have the highest friction?

• Polished marble floor

• Wooden floor

• Sandy road

• Ice

Friction depends on:

• The weight of the object

• The roughness of the surfaces in contact

• Both (a) and (b)

• Neither (a) nor (b)

Friction can be reduced by:

• Making surfaces rougher

• Applying lubricants

• Increasing the weight

• Using rough materials

Why is friction considered a "necessary evil"?

• It only causes problems

• It is harmful in every situation

• It helps in some activities but also causes wear and tear

• It never helps in daily life

Which of the following is an example of useful friction?

• Slipping on a wet floor

• Brakes applied in a moving vehicle

• Sliding a book across a table

• None of the above

Which factor does not directly affect friction?

• Roughness of the surface

• Speed of the object

• Weight of the object

• Surface area in contact

How does friction affect machines?

• Increases efficiency

• Causes wear and tear

• Decreases wear and tear

• Has no effect

Which type of friction is the hardest to overcome?

• Rolling friction

• Sliding friction

• Static friction

• Fluid friction

Friction is reduced in streamlined shapes by:

• Increasing the roughness

• Decreasing the roughness

• Applying more pressure

• None of the above