Home
Class 12
PHYSICS
A bar magnet has coercivity 4xx10^(3) Am...

A bar magnet has coercivity `4xx10^(3) Am^(-1)`. It is desired to demagnetise it by inserting it inside a solenoid `12 cm` long and having `60` turns. The current that should be sent through the solenoid is

A

8 Å

B

6 Å

C

4.5 Å

D

2 Å

Text Solution

Verified by Experts

H = ni
`i= (4 xx 10^(3) xx 12 xx 10^(-2))/(60) = (12)/(15) xx 10 = (120)/(15) = (40)/(5) = 8 A`
Promotional Banner

Topper's Solved these Questions

  • MAGNETISM AND MATTER

    AAKASH INSTITUTE|Exercise Assignment Section - A Objective Type Questions (One option is correct)|58 Videos

  • MAGNETISM AND MATTER

    AAKASH INSTITUTE|Exercise Assignment Section - B Objective Type Questions (One option is correct)|30 Videos

  • MAGNETISM AND MATTER

    AAKASH INSTITUTE|Exercise ASSIGNMENT (SECTION D)|26 Videos

  • LAWS OF MOTION

    AAKASH INSTITUTE|Exercise Assignment (SECTION-D) (Assertion-Reason Type Questions)|15 Videos

  • MECHANICAL PROPERTIES OF FLUIDS

    AAKASH INSTITUTE|Exercise SECTION - J|9 Videos

Similar Questions

Explore conceptually related problems

A bar magnet having coercivity 4 xx 10^(3) Am^(-1) is demagnetised by inserting it inside a solenoid 10 cm long and having 50 turns. The current that should be sent through the solenoid is

A bar magnet has a coercivity 8xx10^(3)A//m . It is desired to damagnetise it by inseting it inside a slenoid 6 cm long and having 60 turns. The current carreid by the solenoid should be

A bar magnet has a coercivity of (4000 Am^-1) It is desired to demagnetize by inserting it inside a solenoid 10 cm long and having 500 turns. The current which should be carried by solenoid is Consider ideal solenoid)

The coercivity of a bar magnet is 120A//m . It is to be demagnetised by placing it inside a solenoid of length 120cm and number of turns 72. The current (in A) flowing through the solenoid is:

The coercivity of a small bar magnet is 4xx10^3Am^(-1) . It is inserted inside a solenoid of 500 turns and length 1 m to demagnetize it. The amount of current to be passed through the solenoid will be

A bar magnet is demagnetized by inserting it inside a solenoid of length 0.2 m, 100 turns, and carrying a current of 5.2 A. The coercivity of the bar magnet is :

The coercivity of a certain permanent magnet is 4*0xx10^4Am^-1 . This magnet is placed inside a solenoid 15cm long and having 600turns . Calculate the current required to demagnetise the magnet completely.

The strength of the magnetic field in a long solenoid having 5000 turns per meter is 3.14x 10^(-2)T . The current flowing through the solenoid is

A long solenoid of 50 cm length having 100 turns carries a current of 2.5A. The magnetic field at centre of solenoid is:

AAKASH INSTITUTE-MAGNETISM AND MATTER -Try Yourself
  1. Relative permeability of iron is 5500 . What is its magnetic susceptib...

    Text Solution

    |

  2. A magnetising field of 1600 Am^(-1) produces a magnetic flux 2.4 xx 10...

    Text Solution

    |

  3. A bar magnet has coercivity 4xx10^(3) Am^(-1). It is desired to demagn...

    Text Solution

    |

  4. A specimen of iron of permeability 8 xx 10^(-3) weber/A m is placed in...

    Text Solution

    |

  5. Calculate magnetic field due to a bar magnet 2 cm long having pole str...

    Text Solution

    |

  6. A bar magnet of magnetic dipole moment 8 Am^(2) has poles separated by...

    Text Solution

    |

  7. A thin bar magnet has dipole moment M . If this is bent in the form of...

    Text Solution

    |

  8. The magnitude of earth magnetic field at magnetic equator is 2.8 xx 10...

    Text Solution

    |

  9. What is the magnitude of the equational and axial fields due to a bar ...

    Text Solution

    |

  10. Calculate torque acting on a bar magnet of length 20 cm magnetic dipol...

    Text Solution

    |

  11. A short bar magnet is kept in uniform magnetic field of 0.16T such tha...

    Text Solution

    |

  12. A circular coil of 60 turns and radius 4 cm carries current of 1 A . H...

    Text Solution

    |

  13. A bar magnet of magnetic dipole moment 10 Am^(2) is in stable equilibr...

    Text Solution

    |

  14. The true value of dip at a place is 30^(@) . The vertical plane carry...

    Text Solution

    |

  15. A magnet suspended at 30^@ with magnetic meridian makes an angle of 45...

    Text Solution

    |

  16. A ship is sailing due west according to Mariner's compass . If the dec...

    Text Solution

    |

  17. If phi(1) and phi(2) be the apparent angles of dip observed in two ver...

    Text Solution

    |

  18. A magnet is pointing towards geographic north at a place where horizon...

    Text Solution

    |

  19. The time period of a mass suspended from a spring is T if the spring i...

    Text Solution

    |

  20. A magnet makes 40 oscillations per minute at a place having magnetic f...

    Text Solution

    |