A circular disc rotates at n rpm. The angular velocity of a circular ring of same mass and radius as the disc and to have the same angular momentum is___________________?

Related Mcqs:

1. If a flywheel increases its speed from 10 rpm to 20 rpm in 10 seconds, then its angular acceleration is_____________________?

   A. —rad/sec 10
   B. —rad/sec 20
   C. —rad/sec 30
   D. none of the above

2. A disc of mass 4 kg, radius 0.5m and moment of inertia 3 kg-m2 rolls on a horizontal surface so that its center moves with speed 5 m/see. Kinetic energy of the disc is ___________________?

   A. 50 J
   B. 150 J
   C. 200 J
   D. 400 J

3. The total kinetic energy of a hoop of mass 2 kg and radius 4 m sliding with linear velocity 8 m/sec and angular velocity 5 radian/sec is_________________?

   A. 64 J
   B. 400 J
   C. 464 J
   D. 89 J

4. A shell travelling with a horizontal velocity of 100 m/sec explodes and splits into two parts, one of mass 10 kg and the other of 15 kg. The 15 kg mass drops vertically downward with initial velocity of 100 m/sec and the 10 kg mass begins to travel at an angle to the horizontal of tan”1 x, where x is______________________?

   A. 3/4
   B. 4/5
   C. 5/3
   D. 3/5

5. The angular speed of a car while taking a circular turn of radius 100m at 36 km/hour, is_______________?

   A. 0.1 radian/sec
   B. 1 radian/sec
   C. 100 radian/sec
   D. 1000 radian/sec

6. The angular speed of a car taking a circular turn of radius 100 m at 36 km/hr will be___________________?

   A. 0.1 rad/sec
   B. 1 rad/sec
   C. 10 rad/sec
   D. 100 rad/sec

7. Rate of change of angular momentum is equal to_______________?

   A. force
   B. torque
   C. linear momentum
   D. impulse

8. A symmetrical body is rotating about its axis of symmetry, its moment of inertia about the axis of rotation being 2 kg -m2 and its rate of rotation 2 revolutions/see. The angular momentum of the body in kg-m2/sec is_____________________?

   A. 4
   B. 6 7i
   C. 8TC
   D. 8

9. If the angular distance, 0 = 2t3 – 3t2, the angular acceleration at t = 1 sec. is__________________?

   A. 1 rad/sec2
   B. 4 rad/sec2
   C. 6 rad/sec2
   D. 12 rad/sec2

10. Two circular discs of same weight and thickness are made from metals having different densities. Which disc will have the larger rotational inertia about its central axis ?

    A. disc with larger density
    B. disc with smaller density
    C. both discs will have same rotational inertia
    D. none of the above