What is meant by the term streamlining?
Improving an object so it can brake faster.
When a car brakes on ice and slides.
Putting slick tyres on a car so it can go faster.
Shaping an object to reduce air or water resistance.
When a body is sliding over other body with a constant speed, the force of friction acting on it is
Static friction.
Limiting friction.
Dynamic friction.
Rolling friction.
Powder is used in carrom board for
Increasing friction.
Decreasing friction.
Decoration.
Fragrance.
Which of the following is not a method used for reducing friction
Use of lubricant.
Polishing the surfaces.
Streamlining.
Making the surface rough..
Which of the following material is likely to have least friction?
Wood.
Plastic.
Glass.
Paper.
Which of the following statements is correct about frictional force?
It exists only for moving bodies.
It exists only for bodies which are at rest
It exists for both moving and non-moving bodies
None of these
How does the proper inflation of tyre save fuel?
Normal reaction decreases
Normal reaction increases
Sliding contact with the road decreases
Sliding contact with the road increases
Which of the following describe a frictional force?
I. Frictional force always opposes the motion of an object
II. Frictional force is parallel to the surface in contact.
III. Frictional force always produces heat.
IV. Frictional force can be increased or reduced.
I and II only
III and IV only
I, II and III only
I, II and IV only
Friction is force. How is friction caused?
One surface moving.
Two surfaces being pushed together.
Two surfaces being rubbed together.
Two surface being pulled apart.
