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A loosely wound helix made of stiff meta...

A loosely wound helix made of stiff metal wire is mounted vertically with the lower end just touching the mercury in a dish. When the current from a battery is started in the metal wire through the mercury. then the spring

A

Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.

B

Both 'A' and 'R' are true and 'R' is not the correct explanation of 'A'

C

'A' is true and 'R' is false

D

'A' is false and 'R' is false

Text Solution

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The correct Answer is:
A
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AAKASH SERIES-MOVING CHARGES AND MAGNETISM-EXERCISE-IB
  1. (A) : A loosely wound helix made of stiff wire is suspended vertically...

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  2. Assertion : The magnetic field at the ends of a very long current carr...

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  3. A loosely wound helix made of stiff metal wire is mounted vertically w...

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  4. A magnetic needls is kept in a non-unifrom magnetic field . It exper...

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  5. Assertion: A flexible wire loop of irregular shape carrying current ...

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  6. (A) : A current carrying circular loop, free to turn, when placed in a...

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  7. Ampere's circuital law is given by

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  8. Deduce the expression for the magnetic dipole moment of an electron or...

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  9. (A) : The microscopic roots of magnetism can be traced back to intrins...

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  10. (A) : The magnetic field at the centre of a circular coil carrying cur...

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  11. A long solonoid carrying a current produces a magnetic field along its...

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  12. (A) : The magnetic field at the centre of a circular coil carrying cur...

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  13. Ratio of magnetic dipole moment to the angular momentum for hydrogen l...

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  14. Assertion: When radius of circular loop carrying current is doubled, i...

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  15. Assertion : A planar circular loop of area A and carrying current I is...

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  16. Assertion : A charged particle can be accelerated in a cyclotron by th...

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  17. Magnetic induction at a point due to a small element of current carryi...

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  18. A current I flows along an inflinitely long straight thin walled tube....

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  19. (A) : Ampere's law holds for steady currents in straight conductor whi...

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  20. (A) : A spark occur between the poles of a switch when the switch is o...

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