Coefficient of friction depends on__________________?

Related Mcqs:

1. The time period of a simple pendulum depends on__________________?

   1) mass of suspended particle
   2) length of the pendulum
   3) acceleration due to gravity
   The correct answer is

   A. only (1)
   B. both (2) and (3)
   C. both (1) and (3)
   D. all are correct

2. The torque produced by a force depends on__________________?

   1) the magnitude of the force
   2) the direction of the force
   3) the’point of application of the force relative to origin
   The correct answer is?

   A. only (1)
   B. both (1) and (2)
   C. both (1) and (3)
   D. all (1), (2) and (3)

3. A rope is wrapped twice around a rough pole with a coefficient of friction ‘A . It is subjected to a force Fj at one end and a gradually increasing force F2 is applied at the other end till the rope just starts slip-ping. At this instant the ratio of F2 to Fi is_____________________?

   A. 1
   B. e2*
   C. e4*
   D. e*72

4. A ladder of weight ‘w’ rests against a smooth vertical wall, and rests on rough horizontal ground, the coefficient of friction between the ladder and the ground being 1/4. The maximum angle of inclination of the ladder to the vertical, if a man of weight ‘w’ is to walk to the top of it safely, is tan’1 x, where x is___________________?

   A. 1/4
   B. 1/3
   C. 3
   D. 4

5. A cylinder will slip on an inclined plane of inclination 0 if the coefficient of static friction between plane and cylinder is_____________________?

   A. less than (1/3) tan 0
   B. less than (2/3) tan 0
   C. less than (1/3) sin 6
   D. less than (2/3) sin 6

6. A car goes round a curve of radius 100 m at 25 m/sec. The angle to the horizontal at which the road must be banked to prevent sideways friction on the car wheels is tan”1 x, where x is (Assume g = 10 m/sec2)_____________________?

   A. 3/8
   B. 1/2
   C. 9/5
   D. 5/8

7. If a body is lying on a plane whose inclination with the horizontal is less than the angle of friction, then___________________?

   1) a force is required to move the body upwards
   2) a force is required to move the body downward
   3) the body will not be in equilibrium
   The correct answer is?

   A. only (1)
   B. only (2)
   C. both (1) and (2)
   D. both (1) and (3)

8. A particle is dropped from a height of 3 m on a horizontal floor, which has a coefficient of restitution with the ball of 1/2. The height to which the ball will rebound after striking the floor is____________________?

   A. 0.5 m
   B. 0.75 m
   C. 1.0 m
   D. 1.5 m

9. Two balls of masses 3 kg and 6 kg are moving with velocities of 4 m/sec and 1 m/sec respectively, towards each other along the line of their centers. After impact the 3 kg ball comes to rest. This can happen only if the coefficient of restitution between the balls is____________________?

   A. 2/3
   B. 1/5
   C. 3/5
   D. 1/3

10. A ball is dropped from a height of 16 m on a horizontal floor. If it rebounds to a height of 9 m after striking the floor, the coefficient of restitution between ball and floor is_____________________?

    A. 1/4
    B. 2/3
    C. 3/4
    D. 4/3