Physics · 2025
JEE Main · 29 January 2025, Shift 1 · Q36
Consider a long straight wire of a circular cross-section (radius a) carrying a steady current I. The current is uniformly distributed across this…
Consider a long straight wire of a circular cross-section (radius a) carrying a steady current I. The current is uniformly distributed across this cross-section. The distances from the centre of the wire's cross-section at which the magnetic field [inside the wire, outside the wire] is half of the maximum possible magnetic field, any where due to the wire, will be
Official answer
From NTA’s final answer key for this paper.
(4)
[a/$\displaystyle 2$, 2a]
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.