p. 25-35

Question 1

The force which opposes the movement or the tendency of movement.

Answer 1

Frictional force/friction

Question 2

The limiting value of frictional force when the motion is impending is known as ________.

Answer 2

Limiting Friction

Question 3

When the applied force is less than the limiting friction, the body remains at
rest and such frictional force is called _______.

Answer 3

Static Friction

Question 4

If the value of applied force exceeds the limiting friction, the body starts moving over the other body and the frictional resistance experienced by the
body while moving is known as ____________.

Answer 4

Dynamic Friction

Question 5

Two types of dynamic friction

(SnR)

Answer 5

Sliding Friction
Rolling Friction

Question 6

It is the friction experienced by a body when it slides over the other body.

Answer 6

Sliding friction

Question 7

It is the friction experienced by a body when it rolls over a surface.

Answer 7

Rolling friction

Question 8

It is experimentally found that the magnitude of limiting friction bears a
constant ratio to the normal reaction between two surfaces.

Answer 8

Coefficient of Friction

Question 9

The force of friction always acts in a direction _______ to that in which body tends to move.

Answer 9

opposite

Question 10

Till the limiting value is reached, the magnitude of friction is exactly ______ to
the force which tends to move the body.

Answer 10

equal

Question 11

The force of friction depends upon the ______/______ of the surfaces.

Answer 11

roughness/smoothness

Question 12

After the body starts moving, the dynamic friction comes into play, the
magnitude of which is less than that of limiting friction and it bears a constant
ratio with normal force. This ratio is called __________.

Answer 12

coefficient of dynamic friction

Question 13

The maximum
inclination of the plane on which a body, free from external forces, can repose is called ________.

Answer 13

Angle of Repose

Question 14

Coplanar parallel forces when act in the same direction.

Answer 14

Like parallel forces

Question 15

Coplanar parallel forces when act in different direction.

Answer 15

Unlike parallel forces

Question 16

Anticlockwise couple

Answer 16

Positive

Question 17

Clockwise couple

Answer 17

Negative

Question 18

It is that point through which the resultant of the distributed gravity force passes regardless of the orientation of the body in space.

Answer 18

Centre of gravity

Question 19

It lies on the axis of symmetry if it exits.

Answer 19

Centroid

Question 20

The force of friction is independent of the ______ between the two surfaces.

Answer 20

area of contact

Question 21

It is the angle which the normal force N makes with the contact force when the equilibrium is limiting.

Answer 21

Angle of Friction

Question 22

It is defined as the angle between the resultant reaction and the normal to
the plane on which the motion of the body is impending.

Answer 22

Angle of Limiting Friction

Question 23

Two unlike equal parallel forces form a ______.

Answer 23

couple

Question 24

The rotational effect of a couple is measured by its ______.

Answer 24

moment