Permanent magnetismHard
Question
What should be amount of current through the ring of radius of 5 cm so that field at the centre equal to the eatrh′s magnetic field of 7 × 10-5 Wb/m2, is
Options
A.0.28amp
B.5.57amp
C.2.8amp
D.none of these
Solution
Maginetic field at the centre of a coil carrying current.
B =
7 × 10-5 =
i =
= 5.57 ampCreate a free account to view solution
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