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An electromagnetic wave going through vacuum is described by

E = E_{0} sin (kx − ωt); B = B_{0} sin (kx − ωt).

Which of the following equations is true?

#### Options

E

_{0}k = B_{0}ωE

_{0}B_{0}= ωkE

_{0 }ω = B_{0}kNone of these

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#### Solution

**E _{0} k = B_{0} ω**

**Explanation:**

The relation between E_{0} and B_{0}_{ }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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