250+ TOP MCQs on Friction of Pivot and Collar Bearing and Answers

Machine Kinematics Multiple Choice Questions on “Friction of Pivot and Collar Bearing”.

1. The power from the engine to the rear axle of an automobile is transmitted by means of
a) worm and worm wheel
b) spur gears
c) bevel gears
d) hooke’s joint
Answer: d
Clarification: A Hooke’s joint is used to connect two shafts, which are intersecting at a small angle. In automobiles, the power is transmitted through this only.

2. A force acting in the opposite direction to the motion of the body is called force of friction.
a) True
b) False
Answer: a
Clarification: The force of friction always acts in a direction, opposite to that in which the body tends to move.

3. The maximum frictional force, which comes into play, when a body just begins to slide over the surface of the other body, is known as
a) static friction
b) dynamic friction
c) limiting friction
d) coefficient of friction
Answer: c
Clarification: The friction, experienced by a body, when at rest, is known as static friction.
The friction, experienced by a body, when in motion, is known as dynamic friction.
The maximum frictional force, which comes into play, when a body just begins to slide over
the surface of the other body, is known as limiting friction.

4. The friction experienced by a body, when at rest, is known as static friction.
a) True
b) False
Answer: a
Clarification: The friction, experienced by a body, when at rest, is known as static friction.
The friction, experienced by a body, when in motion, is known as dynamic friction.
The maximum frictional force, which comes into play, when a body just begins to slide over
the surface of the other body, is known as limiting friction.

5. The dynamic friction is the friction experienced by a body, when the body
a) is in motion
b) is at rest
c) just begins to slide over the surface of the other body
d) none of the mentioned
Answer: a
Clarification: The friction, experienced by a body, when at rest, is known as static friction.
The friction, experienced by a body, when in motion, is known as dynamic friction.
The maximum frictional force, which comes into play, when a body just begins to slide over
the surface of the other body, is known as limiting friction.

6. The static friction
a) bears a constant ratio to the normal reaction between the two surfaces
b) is independent of the area of contact, between the two surfaces
c) always acts in a direction, opposite to that in which the body tends to move
d) all of the mentioned
Answer: d
Clarification: The laws of static friction are:
a) The force of friction always acts in a direction, opposite to that in which the body tends to move.
b) The magnitude of the force of friction is exactly equal to the force, which tends to move.
c) The force of friction is independent of the area of contact, between the two surfaces.
d) The force of friction depends upon the roughness of the surfaces.

7. Which of the following statements regarding laws governing the friction between dry surfaces are correct?
a) The friction force is dependent on the materials of the contact surfaces.
b) The friction force is directly proportional to the normal force.
c) The friction force is independent of the area of contact.
d) All of the mentioned
Answer: d
Clarification: The laws of friction between dry surfaces are:
a) The force of friction always acts in a direction, opposite to that in which the body tends to move.
b) The magnitude of the force of friction is exactly equal to the force, which tends to move.
c) The force of friction is independent of the area of contact, between the two surfaces.
d) The force of friction depends upon the roughness of the surfaces.

8. The angle of the inclined plane at which the body just begins to slide down the plane, is called helix angle.
a) True
b) False
Answer: b
Clarification: The angle of the inclined plane at which the body just begins to slide down the plane, is called angle of repose.

9. The angle which the normal reaction makes with the resultant reaction is called angle of friction.
a) True
b) False
Answer: a
Clarification: The angle of the inclined plane at which the body just begins to slide down the plane, is called angle of repose. The angle which the normal reaction makes with the resultant reaction is called angle of friction.

10. The angle of inclination of the plane, at which the body begins to move down the plane is called
a) angle of friction
b) angle of repose
c) angle of projection
d) none of the mentioned
Answer: b
Clarification: The angle of the inclined plane at which the body just begins to slide down the plane, is called angle of repose. The angle which the normal reaction makes with the resultant reaction is called angle of friction.