Tangent of angle of friction is equal to__________________?

Related Mcqs:

1. 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 ).

2. 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

3. 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

4. Friction force for dry surfaces. Friction force is________________?

   Pick up wrong statement?
   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

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. Angle of 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

7. The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of_______________?

   A. friction
   B. limiting friction
   C. repose
   D. kinematic friction
   E. static friction

8. If two equal forces of magnitude P act at an angle 9°, their resultant will be________________?

   A. P/2 cos 9/2
   B. IP sin 9/2
   C. 2P tan 9/2
   D. IP cos 9/2
   E. Psin 9/2

9. 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

10. 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