A. proportional to normal load between the surfaces
B. dependent on the materials of contact surface
C. proportional to velocity of sliding
D. independent of the area of contact surfaces
E. none of the above is wrong statement
Related Mcqs:
- Dynamic friction as compared to static friction is________________?
A. same
B. more
C. less
D. may be less of more depending on nature of surfaces and velocity
E. has no correlation - A semi-circular disc rests on a horizontal surface with its top flat surface horizontal and circular portion touching down. The coefficient of friction between semi-cricular disc and horizontal surface is i. This disc is to be pulled by a horizontal force applied at one edge and it always remains horizontal. When the disc is about to start moving, its top horizontal force will____________________?
A. remain horizontal
B. slant up towards direction of pull
C. slant down towards direction of pull
D. unpredictable
E. none of the above - Coulomb friction is the friction between_________________?
A. bodies having relative motion
B. two dry surfaces
C. two lubricated surfaces
D. solids and liquids
E. electrically charged particles - The resultant of the following three couples 20 kg force, 0.5 m arm, $ ve sense 30 kg force, 1 m arm, – ve sense 40 kg force, 0.25 m arm, + ve sense having arm of 0.5 m will be_________________?
A. 20 kg, – ve sense
B. 20 kg, + ve sense
C. 10 kg, + ve sense
D. 10 kg, – ve sense
E. 45 kg, + ve sense - Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction__________________?
A. along the plane
B. horizontally
C. vertically
D. at an angle equal to the angle of friction to the inclined plane
E. unpredictable - On the ladder resting on the ground and leaning against a smooth vertical wall, the force of friction will be__________________?
A. downwards at its upper end
B. upwards at its upper end
C. perpendicular to the wall at its upper end
D. zero at its upper end
E. none of the above - On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be__________________?
A. towards the wall at its upper end
B. away from the wall at its upper end
C. upwards at its upper end
D. downwards at its upper end
E. none of the above - Pick up the incorrect statement from the following _______________?
A. The C.G. of a circle is at its center
B. The C.G. of a triangle is at the intersection of its medians
C. The C.G. of a rectangle is at the inter-section of its diagonals
D. The C.G. of a semicircle is at a distance of r/2 from the center
E. The C-G. of an ellipse is at its center - Tangent of angle of friction is equal to_________________?
A. kinetic friction
B. limiting friction
C. angle of repose
D. coefficient of friction
E. friction force - The ratio of limiting friction and normal reaction is known as_______________?
A. coefficient of friction
B. angle of friction
C. angle of repose
D. sliding friction
E. friction resistance
