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Two conducting circular loops A and B are placed in the same plane with their centres coinciding as shown in figure. The mutual inductance between them is: [figure]
(2) 0 a22b
Pass current I in the big loop B. Field at its centre: B = 0 I2b
b a, this field is uniform over the small loop A:
A = B a2 = 0 I a22b
M = AI = 0 a22b
Answer: (2)
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