JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The electric field of an electromagnetic wave travelling through a medium is given by \(\overline{E}(x,t) = 25\ sin(2.0 \times 10^{15}t - 10^{7}x)\hat{n}\) then the refractive index of the medium is ___________.
(All given measurement are in SI units)
- A 1.2
- B 2
- C 1.5
- D 1.7
Answer & Solution
Correct Answer
(C) 1.5
Step-by-step Solution
Detailed explanation
\(\omega = 2 \times 10^{15} rad/s\) \(k = 10^{7} m^{-1}\) \(V =\frac{2 \pi}{ k } \cdot \frac{\omega}{2 \pi}=\frac{\omega}{ k }=\frac{2 \times 10^{15}}{10^7}=2 \times 10^8=\frac{ C }{1.5}\) \(\Rightarrow \mu = 1.5\)
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