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One of the two identical conducting wires of length L is bent in the form of a circular loop and the other one into a circular coil of N identical turns. If the same current is passed in both, the ratio of the magnetic field at the central of the loop (B L ), i.e. L C B B will be :

1. 1 N
2. N
3. N 2
4. 2 1 N

Correct answer: 2 1 N

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