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A bar magnet of moment 40 A-m^(2) is fre...

A bar magnet of moment `40 A-m^(2)` is free to rotate about a vetical axis passing through its centre. The magnet is released from rest from east west direction. The kinetic energy of the magnet as it takes north-south direction is `(B_(H)=30muT)`

A

0.6mJ

B

1.2mJ

C

2.4mJ

D

0.3mJ

Text Solution

Verified by Experts

The correct Answer is:
B
`K.E=W=MB(1-costheta)`
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NARAYNA-MAGNETISM AND MATTER-EXERCISE - 2 (H.W)
  1. A bar magnet of length 10 cm experiences a torque of 0.141 N-m in a un...

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  2. A bar magnet of pole strnegth 2A-m is kept in a magnetic field of indu...

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  3. A magnet of magnetic moment 20(hatk) Am^(2) is placed along the z-axis...

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  4. The torque required to keep a magnet of length 10cm at 45^(@) to a uni...

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  5. A bar magnet of moment 40 A-m^(2) is free to rotate about a vetical ax...

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  6. A bar magnet of magnetic moment M is divided into 'n' equal parts cutt...

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  7. A short bar magnet of magnetic moment 12.8xx10^(-3)Am^(2) is arranged ...

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  8. The magnetic field strength at a point a distance 'd' form the centre ...

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  9. Two north poles each of pole strength 8Am are placed at corners A and ...

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  10. Two short bar magnets of magnetic moments 0.1245 Am^(2) and 0.512 Am^(...

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  11. A bar magnet of moment of inertia I is vibrated in a magnetic field of...

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  12. A bar magnet has moment of inertia 49x10^(2)kgm^(2) vibrates in a magn...

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  13. A thin rod 30 cm long is uniformly magnetised and its period of oscill...

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  14. A magnet freely suspended in a vibration magnetometer makes 10 oscilla...

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  15. A magnetic needle pivoted through its centre of mass and is free to ro...

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  16. The magnetic susceptibility of a medium is 0.825. Its relative permeab...

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  17. A magnetic field strength (H) 3xx10^(3) Am^(-1) produces a magnetic fi...

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  18. The magnetic moment of a magnet of mass 75 gm is 9xx10^(-7) A-m^(2). I...

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  19. A magnetising field of 5000 A/m produces a magnetic flux of 5xx10^(-5)...

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  20. A short bar magnet of magnetic moment 20Am^(2) has a cross sectional a...

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