question_answer

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. If the same current is passed in both, the ratio of the magnetic field at the central of the loop \[({{B}_{L}}),\,\,\,\,i.e.\,\,\,\frac{{{B}_{L}}}{{{B}_{C}}}\]will be: [JEE Main 09-Jan-2019 Evening]

A) \[\frac{1}{N}\]

B) N     

C) \[{{N}^{2}}\]

D) \[\frac{1}{{{N}^{2}}}\]

Correct Answer: D

Solution :

[d]

Option [d] is correct.