Physics · 2026
JEE Main · 28 January 2026, Shift 1 · Q41
The electric field of an electromagnetic wave travelling through a medium is given by E (x, t)=25 sin (2.0 × 10^15 t-10^7 x) n then the refractive…
The electric field of an electromagnetic wave travelling through a medium is given by $\displaystyle \vec{E}(x, t)=25 \sin \left(2.0 \times 10^{15} t-10^7 x\right) \hat{n}$then the refractive index of the medium is $\displaystyle \_\_\_\_$.
(All given measurement are in SI units)
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 1.5$
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JEE Main 2026 Physics question, with the answer from NTA’s final answer key. Where our answers come from.