A long conducting wire having a current I flowing through it, is bent into a circular coil of N turns. Then it is bent into a circular coil of n turns. The magnetic field is calculated at the centre of coils in both the cases. The ratio of the magnetic field in first case to that of second case is:
Held on 31 Jan 2023 · Verified 6 Jul 2026.
N:n
n2:N2
N2:n2
n:N
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