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An electromagnetic wave propagating in free space is represented by E = E₀ sin(kx − ωt) and B = B₀ sin(kx − ωt). Which of the following relations is correct?

1. E₀k = B₀ω
2. E₀ω = B₀k
3. E₀B₀ = ωk
4. None of these

Correct answer: E₀k = B₀ω

Solution

In free space E0/B0 = c and c = omega/k, so E0/B0 = omega/k, i.e. E0*k = B0*omega.

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