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A circular coil of radius 'r' having 'n'...

A circular coil of radius `'r'` having `'n'` turns carries a current `'I'`. The magnetic induction at the center of the coil is `'B'`. Now the coil is unwound and rewound with half the original radius. If the magnetic induction at the center of the coil is to be the same, the current that should be passed through the coil is

A

2i

B

i

C

i/2

D

i/4

Text Solution

Verified by Experts

The correct Answer is:
D
`n_1 r_1 = n_2 r_2 , B = (mu_0 "ni" )/(2r)`
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NARAYNA-MOVING CHARGES AND MAGNETISM-EXERCISE - 2(C.W) (AMPERE.S CIRCUITAL LAW BIO-SAVART LAW AND ITS APPLICATIONS)
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  15. Magnetic field induction at the center of a circular coil of radius 5c...

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