A) \[\text{2}\,{{\text{m}}^{\text{-1}}}\]
B) \[\text{0}\text{.5}\,{{\text{m}}^{\text{-1}}}\]
C) \[6\,{{\text{m}}^{\text{-1}}}\]
D) \[3\,{{\text{m}}^{\text{-1}}}\]
Correct Answer: A
Solution :
Electromagnetic wave equation \[E={{E}_{0}}\cos (kz-\omega t)\] ?(i) Speed of electromagnetic wave \[v=\frac{\omega }{k}\] Given, equation\[E=i\,40\cos (kz-6\times {{10}^{8}}t)\]?(ii) Comparing Eqs. (i) and (ii), we get \[\omega =6\times {{10}^{8}}\]and\[{{E}_{0}}=40i\]Here, wave factor \[k=\frac{\omega }{v}=\frac{6\times {{10}^{8}}}{3\times {{10}^{8}}}=2{{m}^{-1}}\]You need to login to perform this action.
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