A circular loop of radius R is carrying current iA. The ratio of magnetic field at the centre of circular loop and at a distance R from the center of the loop on its axis is :
Held on 24 Jan 2023 · Verified 6 Jul 2026.
1:32
32:2
22:1
1:2
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A short bar magnet placed with its axis at $30^{\circ}$ with an external field of 800 Gauss, experiences a torque of $0.016 \mathrm{~N}. \mathrm{m}$. The work done in moving it from most stable to most unstable position is $\alpha \times 10^{-3} \mathrm{~J}$. The value of $\alpha$ is $\_\_\_\_$.
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