The ratio of limiting friction and normal reaction is known as_______________?

Related Mcqs:

1. 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

2. 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

3. Pick up wrong statement about friction force for dry surfaces. Friction force is________________?

   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

4. Angle oT friction is the___________________?

   A. angle between normal reaction and the resultant of normal reaction and the limiting friction
   B. ratio of limiting friction and normal reaction
   C. the ratio of minimum friction force to the friction force acting when the body is just about to move
   D. the ratio of minimum friction force to friction force acting when the body is in motion
   E. ratio of static and dynamic friction

5. 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

6. Kinetic friction is the________________?

   A. tangent of angle between normal reac-tion and the resultant of normal reac-tion and the limiting friction
   B. ratio of limiting friction and normal reaction
   C. the friction force acting when the body is just about to move
   D. the friction force acting when the body is in motion
   E. dynamic friction

7. 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

8. The co-efficient of friction depends upon________________?

   A. nature of surfaces
   B., area of contact
   C. shape of the surfaces
   D. ail of the above.
   E. A. and B. above

9. A particle inside a hollow sphere of radius r, having coefficient of friction -rr can rest upto height of__________________?

   A. r/2
   B. r/A
   C. r/%
   D. 0.134 r
   E. 3r/8

10. The effort required to lift a load W on a screw jack with helix angle a and angle of friction <j) is equal to_________________?

    A. Wtan(a + )
    B. Wtan(a-)
    C. Wcos(a + )
    D. Wsin(a + )
    E. W (sin a + cos )