The same current is passed through two identical conducting wires of the same length L. One of them, w1, is bent in the form of a circular loop of N1 turns while the other wire, w2, is bent in the form of a circular loop of N2 turns. The ratio of the magnetic fields at the centre of the coils w1 and w2 will be -
1
\(\frac{{{N_1}}}{{{N_2}}}\)
2
\(\frac{{{N_2}}}{{{N_1}}}\)
3
\({\left( {\frac{{{N_1}}}{{{N_2}}}} \right)^2}\)
4
\({\left( {\frac{{{N_2}}}{{{N_1}}}} \right)^2}\)