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Physics · PYQ NEET UG 2016(2)
हिन्दीA long wire carrying a steady current is bent into a circular loop of one turn. The magnetic field at the centre of the loop is B. It is then bent into a circular coil of n turns. The magnetic field at the centre of this coil of n turns will be
Correct answer · Option 3
\( n^2B \)
Explanation
Magnetic field \( B = \frac{\mu_0 I}{2R} \). For \( n \) turns, radius becomes \( R/n \) and field becomes \( B' = \frac{\mu_0 n I}{2(R/n)} = n^2 B \).
