CBSE 2023 · Region 2 · Set 1 · Q6 · 1 mark

A long straight wire of radius 'a' carries a steady current ' $\displaystyle I$ '. The current is uniformly distributed across its area of cross-section. The ratio of magnitude of magnetic field $\displaystyle \overrightarrow{\mathrm{B}}_{1}$ at $\displaystyle \frac{\mathrm{a}}{2}$ and $\displaystyle \overrightarrow{\mathrm{B}}_{2}$ at distance $\displaystyle 2$ a is

CBSE Class 12 Physics past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.