Understanding Friction

Why is friction important for walking on a slippery road?

• It increases the speed of walking.

• It provides the necessary grip to prevent slipping.

• It makes the road smoother.

• It reduces the weight of the person walking.

What is the primary factor that affects the magnitude of friction between two surfaces?

• The color of the surfaces

• The temperature of the environment

• The nature of the surfaces in contact

• The weight of the objects

Which type of friction occurs when an object is stationary?

• Fluid friction

• Static friction

• Rolling friction

• Kinetic friction

How does streamlining help in reducing fluid friction?

• By increasing the weight of the object

• By changing the color of the object

• By increasing the speed of the object

• By reducing the surface area in contact with the fluid

Why do pencils write on paper?

• Due to the smoothness of the paper

• Because of the color of the lead

• Due to the friction between the lead and paper

• Because of the weight of the pencil

What is the purpose of treads on tires?

• To increase the speed of the vehicle

• To make the tires look attractive

• To increase friction and improve grip on the road

• To reduce the weight of the vehicle

How does friction affect machines with moving parts?

• It causes wear and tear over time.

• It makes them run faster.

• It makes them more colorful.

• It reduces their weight.

What happens when friction is reduced between the wheels of a vehicle and the road?

• The wheels slide instead of rolling, causing skidding.

• The vehicle speeds up.

• The vehicle becomes heavier.

• The vehicle changes color.

What is the role of lubricants in machines?

• To reduce friction and ensure smooth operation

• To increase the weight of the machine

• To make the machine more colorful

• To increase the speed of the machine

Why are ball bearings used in cycles and cars?

• To increase the speed of the vehicle

• To make the vehicle more colorful

• To increase the weight of the vehicle

• To reduce friction in rotating parts