Sahay Sir > Question Answers > NEET Last 32 Years Solved 1988 - 2019 Physics and Chemistry Video Solutions > Physics > Chapter 23 - Magnetic Effects of Current and Moving Charges > A long straight wire of radius a carries a steady current I. The current is uniformly distributed over its cross-section. The ratio o the magnetic fields B and B′, at radial distances a/2 and 2a respectively, from the axis of the wire is

A long straight wire of radius a carries a steady current I. The current is uniformly distributed over its cross-section. The ratio o the magnetic fields B and B′, at radial distances a/2 and 2a respectively, from the axis of the wire is

A long straight wire of radius a carries a steady current I. The current is uniformly distributed over its cross-section. The ratio o the magnetic fields B and B′, at radial distances a/2​ and 2a respectively, from the axis of the wire is