Physics · 2025
JEE Main · 28 January 2025, Shift 2 · Q26
A bar magnet has total length 2 l=20 units and the field point P is at a distance d =10 units from the centre of the magnet. If the relative…
A bar magnet has total length $\displaystyle 2 l=20$ units and the field point P is at a distance $\displaystyle \mathrm{d}=10$ units from the centre of the magnet. If the relative uncertainty of length measurement is $\displaystyle 1$%, then uncertainty of the magnetic field at point P is :
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle 3$%
(2)
$\displaystyle 4$%
NTA’s answer key accepts either.
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.