11th class (Fsc) Physics unit 5 MCQs
26. 1 rev / min is equal to:
a. 𝜋/20 rads-1
b. 𝜋/6 rads-1
c. 𝜋/30 rads-1
d. 𝜋/15 rads-1
27. The direction of angular velocity is determined by:
a. Right hand rule
b. Left hand rule
c. General rule
d. Head to tail rule
28. The angular velocity of the minute hand of a clock is:
a. 𝜋/60 rads-1
b. 2𝜋 rads-1
c. 𝜋/180 rads-1
d. 𝜋 rads-1
29. The angular speed of a fly wheel making 120 revolutions per minute is:
a. 𝜋 rads-1
b. 2𝜋 rads-1
c. 4𝜋 rads-1
d.120𝜋 rads-1
30. The time rate of change of angular displacement is called:
a. Angular speed
b. Linear velocity
c. Angular velocity
d. Linear speed
31. Angular acceleration is produced by:
a. Pressure
b. Power
c. Force
d.Torque
32. The rate of change of angular velocity is called:
a. Angular displacement
b. Angular velocity
c. Angular speed
d. Angular acceleration
33. Direction of angular acceleration is always along:
a. z-axis
b. x-axis
c. The axis of rotation
d. y-axis
34. When a body moves in a circle, the angle between linear velocity ‘V’ and angular velocity is:
a. 60o
b. 180o
c. 45o
d. 90o
35. The motion of a body moving along a circular path is called:
a. Linear motion
b. Translation motion
c. Vibratory motion
d. Angular motion
36. Which one of the following is correct?
a. v= rꞷ
b. ꞷ= rv
c. ꞷ= r/v
d. v= r/ꞷ
37. A wheel of radius 50cm having an angular speed of 5 rad/s have linear speed:
a. 4.5 m/s
b. 1.5 m/s
c. 2.5 m/s
d. 3.5 m/s
38. The ratio of angular frequency and linear frequency is:
a. 1/2𝜋
b. 2𝜋
c. 2/𝜋
d. 𝜋
39. When a particle is moving along a circular path, its projection along the diameter executes:
a. Rotatory motion
b. Linear motion
c. SHM
d. Vibratory motion
40. The magnitude of centripetal force on a mass ‘m’ moving with angular speed ‘m’ in a circle of radius r is:
a. mr ꞷ2
b. mr2 ꞷ
c. mr2 ꞷ2
d. mw2/r
41. Centripetal acceleration is also called:
a. Angular
b. Tangential
c. Rotational
d. Radial
42. When a body is whirled in a horizontal circle by means of string. The centripetal force supplied by:
a. Tension in the string
b. Mass of a body
c. Centripetal acceleration
d. Velocity of a body
43. Which of the following is not directing along the fixed axis of rotation?
a. Centripetal acceleration
b. Angular displacement
c. Angular acceleration
d. Angular momentum
44. If a body revolves under centripetal force, its angular acceleration is:
a. Increasing
b. Non zero
c. Zero
d. Variable
45. Centripetal force performs:
a. Negative work
b. Maximum work
c. No Work
d. Minimum work
46. The centripetal force is always directed:
a. Opposite to the motion of the body
b. Away from the centre along the radius
c. Towards the centre along the radius
d. Along the direction of motion
47. Which one of the following is not directed along the axis of rotation?
a. Centripetal acceleration
b. Angular acceleration
c. Angular displacement
d. Angular momentum
48. If linear velocity and radius are both made to half of a body moving around a circle. There its centripetal force becomes:
a. Fc/4
b. Fc
c. 2Fc
d. Fc/2
49. Which one of the following force cannot do any work on the particle on which it acts?
a. Electrostatic force
b. Fractional force
c. Centripetal force
d. Gravitational force
50. The diver spins faster when moment of inertia becomes:
a. Constant
b. Smaller
c. Equal
d. Greater