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PhysicsJEE Main 28 Jan 2026, Shift 1·Q7·MCQ·Easy–moderate

Electromagnetic Waves · EM waves

The electric field of an electromagnetic wave travelling through a medium is given by E⃗(x,t)=25sin⁡(2.0×1015t−107x) n^\vec E(x,t) = 25\sin(2.0\times10^{15}t - 10^{7}x)\,\hat n then the refractive index of the medium is .
(All given measurements are in SI units)
  1. (1)1.2
  2. (2)2
  3. (3)1.5
  4. (4)1.7
We corrected a printing error in the original paper

Source printed “All given measurement are”.

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