Home
Class 11
PHYSICS
A bar magnet is hung by a thin cotton th...

A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equilibrium state. The energy required to rotate it by 60^(@) is W. Now the torrue required to keep the magnet in this new position is

A

`(2W)/(sqrt3)`

B

`(W)/(sqrt3)`

C

`sqrt3W`

D

`(sqrt3W)/(2)`

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Topper's Solved these Questions

  • MAGNETIC EFFECT OF ELECTRIC CURRENT

    TARGET PUBLICATION|Exercise Evaluation Test|12 Videos

  • MEASUREMENTS

    TARGET PUBLICATION|Exercise EVALUATION TEST|17 Videos

Similar Questions

Explore conceptually related problems

A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in' equilibrium state. The energy required to rotute it by 60^(circ) is W . Now the torque required to keep the magnet in this new: position is sqrt(k) W . Find k .

A bar magnet hung by a insulating thread In a uniform horizontal magnetic field and magnet is in equilibrium Initially. The torque required to keep the magnet at angle by 30° with the direction of magnetic field is t. Then the work done to rotate it by same angle from initial position is

A bar magnet of magnetic moment M is hung by a thin cotton thread in a uniform magnetic field B. Work done by the external agent to rotate the bar magnet from stable equilibrium position to 120° with the direction of magnetic field is (consider change in angular speed is zero)

A magnetic needle lying parallel to a magnetic field requires W units of work to turn through 60^(@) . The external torque required to maintain the magnetic needle in this position is

TARGET PUBLICATION-MAGNETISM-MCQs
  1. A circular loop and a square loop are formed from the same wire and th...

    Text Solution

    |

  2. A charge Q is spread uniformly over an insulated ring of radius R.What...

    Text Solution

    |

  3. At neutral point, the horizontal component of the magnetic field due t...

    Text Solution

    |

  4. Assertion: If a compass needle be kept at magnetic north pole of the e...

    Text Solution

    |

  5. A bar magnet is hung by a thin cotton thread in a uniform horizontal m...

    Text Solution

    |

  6. A circular coil of diameter 10 cm is placed in a magnetic field of ind...

    Text Solution

    |

  7. Assertion: The magnetic poles of earth do not coincide with the geogra...

    Text Solution

    |

  8. The magnetic compass is not useful for navigation near the magnetic po...

    Text Solution

    |

  9. A short bar magnet with its north pole facing north forms a neutral po...

    Text Solution

    |

  10. The angle of dip at a place is delta. If the dip is measured in a plan...

    Text Solution

    |

  11. A short bar magnet is placed in the magnetic meridian with its north p...

    Text Solution

    |

  12. The valence electron in the lithium atom is moving with a speed of 1.8...

    Text Solution

    |

  13. Two short magnets with pole strengths of 100 ab ampere-cm and 64 ab am...

    Text Solution

    |

  14. When magnetised, length of an iron bar

    Text Solution

    |

  15. A bar magnet is placed with its north pole towards geographic north. T...

    Text Solution

    |

  16. A solenoid has a core of inner radius 20 cm and outer radius 22 cm aro...

    Text Solution

    |

  17. Choose the incorrect statement.

    Text Solution

    |

  18. Draw magnetic field lines due to a U-shaped magnet.

    Text Solution

    |

  19. A ship is sailing due west according to Mariner's compass. If thedecli...

    Text Solution

    |

  20. The earth's magnetic field at the equator is approximately 0*4G, Estim...

    Text Solution

    |