Physics · 2025
JEE Main · 28 January 2025, Shift 2 · Q38
An infinite wire has a circular bend of radius a, and carrying a current I as shown in figure. The magnitude of magnetic field at the origin O of the…
An infinite wire has a circular bend of radius a, and carrying a current I as shown in figure. The magnitude of magnetic field at the origin O of the arc is given by :

Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle \frac{\mu_0}{4 \pi} \frac{\mathrm{I}}{\mathrm{a}}\left[\frac{3 \pi}{2}+1\right]$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.