Home
Class 12
PHYSICS
The diameter of a flywheel is 1 m. It ha...

 The diameter of a flywheel is 1 m. It has a mass of 20 kg. It is rotating about its axis with a speed of 120 rotations in 1 min. Its angular momentum in `kg-m^(2)s^(-1)is

A

13.4

B

31.4

C

41.4

D

43.4

Text Solution

Verified by Experts

The correct Answer is:
(b)
`d=2r=1m`
implies` r=0.5m`
`m=20kg`
`n=(120)/(60)=2` rotations//sec
Angular momentum, `L=Iomega`
`=(1)/(2)Mr^(2)xx2pin`
`=(1)/(2)xx20xx0.5^(2)xx2xxpixx2`
`=31.416 kgm^(2)s^(-1)`
Promotional Banner

Topper's Solved these Questions

  • SEMICONDUCTOR ELECTRONICS

    SIA PUBLICATION|Exercise MCQ|90 Videos

  • THERMAL CONDUCTIVITY

    SIA PUBLICATION|Exercise Problems|96 Videos

Similar Questions

Explore conceptually related problems

A uniform solid sphere of diameter 0.2m and mass 10kg is rotated about its diameter with an angular velocity of 2rads^(-1) . Then its angular momentum is kgm^(2)s^(-1) is

If the K.E. of a rotating body about an axis is decreased by 36% , its angular momentum about that axis

A wheel of mass 10 kg has a moment of inertial of 160 kg-m^(2) about its own axis. The radius of gyration is

SIA PUBLICATION-SYSTEM OF PARTICLES AND ROTATIONAL MOTION-MCQ
  1. A body is sliding down a rough inclined plane. The coefficient of fric...

    Text Solution

    |

  2. Particles of masses m, 2m, 3m ... nm gram are placed on the same line ...

    Text Solution

    |

  3. The diameter of a flywheel is 1 m. It has a mass of 20 kg. It is rotat...

    Text Solution

    |

  4. The velocities of three particles of masses 20 g, 30 g and 50 g are 10...

    Text Solution

    |

  5. . A particle is projected up along a rough inclined plane of inclinati...

    Text Solution

    |

  6. A uniform metal rod of length L and mass M is rotating about an axis p...

    Text Solution

    |

  7. From a uniform wire, two circular loops are made (i) P of radius r and...

    Text Solution

    |

  8. A body is sliding down an inclined plane having coefficient of frictio...

    Text Solution

    |

  9. The radius of gyration of a sphere of mass M and radius R about the ax...

    Text Solution

    |

  10. A wheel has a speed of 1200 rev/min and is made to slow down at a rate...

    Text Solution

    |

  11. Two particles of mass 1 kg and 3 kg have position vectors 2hati + 3hat...

    Text Solution

    |

  12. A stone is projected vertically up to reach maximum height h. The rati...

    Text Solution

    |

  13. A body takes 1(1)/(3) times as much time to slide down a rough incline...

    Text Solution

    |

  14. The moment of inertia of a thin uniform rod of mass M and length L abo...

    Text Solution

    |

  15. The position of a particle is given by vecr=(hati+2hatj-hatk)momentum ...

    Text Solution

    |

  16. A thin metal disc of radius 0.25 m and mass 2 kg starts from rest and ...

    Text Solution

    |

  17. A constant torque of 1000 N-m, turns á wheel of moment of inertia 200 ...

    Text Solution

    |

  18. A wheel of mass 10 kg has a moment of inertial of 160 kg-m^(2) about i...

    Text Solution

    |

  19. The moment of inertia of a solid sphere of mass M and radius R about t...

    Text Solution

    |

  20. A bomb travelling in a parabolic path under the effect of gravity, exp...

    Text Solution

    |