Question

An electromagnetic wave going through vacuum is described by E = E_o sin(kx – ωt) then B = B_o sin(kx – ωt) then

(A) E_oB_o = ωk

(B) E_ok = B_oω

(C) E_oω = B_ok 

(D) none of these

Answer 1

The correct option is (B) E_ok = B_oω.

Explanation:

E = E_o sin(kx – ωt)

B = B_o sin(kx – ωt)

we know (E_o / B_o) = C  and  k = (ω/c)

∴ (E_o / B_o) = (ω/k)  hence E_ok = B_oω