Karnataka Board PUCPUC Science 2nd PUC Class 12

An electromagnetic wave going through vacuum is described byE = E0 sin (kx − ωt); B = B0 sin (kx − ωt).Which of the following equations is true? - Physics

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MCQ

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

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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`

  Is there an error in this question or solution?
Chapter 18: Electromagnetic Waves - MCQ [Page 338]

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HC Verma Class 11, Class 12 Concepts of Physics Vol. 2
Chapter 18 Electromagnetic Waves
MCQ | Q 5 | Page 338

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