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Magnetics question

2018 · Shift 0 · Q49

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JEE Main
Physics
Magnetics
2018 · Shift 0 · Q49

Magnetics question

2018 · Shift 0 · Q49

JEE MainPhysicsMagneticsMCQ+4 / −1

The dipole moment of a circular loop carrying a current I, is m and the magnetic field at the centre of the loop is B1. When the dipole moment is doubled by keeping the current constant, the magnetic field at the centre of the loop is

{{B_2}}

. The ratio

{{{B_1}} \over {{B_2}}}

is:

A
2
B
$\sqrt 3$
C
$\sqrt 2$
D
$1 \over \sqrt 2$

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