Question

A wire of length 'ℓ' is used to make a circular coil of 'n' no. of turns. A current 'I' passes through the coil. If twice the length of wire is used now to make the coil with turns of same radius, making same current flow through it, the magnetic field at the centre of coil will become.
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Answer 1

Answer:

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REGARDS

Answer 2

The magnetic field doubles because magnetic field is directly proportional to the no. of turns and to maintain the radius, the no of turns is doubled.

Answer : Magnetic field at the centre doubles