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Question
An electromagnetic wave going through vacuum is described by
E = E0 sin (kx − ωt); B = B0 sin (kx − ωt).
Which of the following equations is true?
Options
E0 k = B0 ω
E0 B0 = ωk
E0 ω = B0 k
None of these
Solution
E0 k = B0 ω
Explanation:
The relation between E0 and B0 is given by `"E"_0/"B"_0 = "C"` ...(1)
Here, c = speed of the electromagnetic wave
The relation between ω (the angular frequency) and k (wave number):
`ω/"k" = "c"` ...(2)
Therefore, from (1) and (2), we get :
`"E"_0/"B"_0 = ω/"k" = "c"`
⇒ `"E"_0"k" = "B"_0ω`
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