p. 25-35 Flashcards
The force which opposes the movement or the tendency of movement.
Frictional force/friction
The limiting value of frictional force when the motion is impending is known as ________.
Limiting Friction
When the applied force is less than the limiting friction, the body remains at
rest and such frictional force is called _______.
Static Friction
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 ____________.
Dynamic Friction
Two types of dynamic friction
(SnR)
Sliding Friction
Rolling Friction
It is the friction experienced by a body when it slides over the other body.
Sliding friction
It is the friction experienced by a body when it rolls over a surface.
Rolling friction
It is experimentally found that the magnitude of limiting friction bears a
constant ratio to the normal reaction between two surfaces.
Coefficient of Friction
The force of friction always acts in a direction _______ to that in which body tends to move.
opposite
Till the limiting value is reached, the magnitude of friction is exactly ______ to
the force which tends to move the body.
equal
The force of friction depends upon the ______/______ of the surfaces.
roughness/smoothness
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 __________.
coefficient of dynamic friction
The maximum
inclination of the plane on which a body, free from external forces, can repose is called ________.
Angle of Repose
Coplanar parallel forces when act in the same direction.
Like parallel forces
Coplanar parallel forces when act in different direction.
Unlike parallel forces
Anticlockwise couple
Positive
Clockwise couple
Negative
It is that point through which the resultant of the distributed gravity force passes regardless of the orientation of the body in space.
Centre of gravity
It lies on the axis of symmetry if it exits.
Centroid
The force of friction is independent of the ______ between the two surfaces.
area of contact
It is the angle which the normal force N makes with the contact force when the equilibrium is limiting.
Angle of Friction
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.
Angle of Limiting Friction
Two unlike equal parallel forces form a ______.
couple
The rotational effect of a couple is measured by its ______.
moment
