Notes

Characteristics of EM Waves…

Characteristics of EM Waves –
(i) Whose speed is same as that of light are the electromagnetic waves transverse in nature.
(ii) They are in phase with each other oscillation of the same frequency have two fields E and B.
(iii) The rate of flow of energy crossing a unit area in an electromagnetic wave is described by the vector S called the Poynting vector, which is defined by the expression
S = 1/μ₀ (E×B)
⇒ S = EB/μ₀ [∴ E ⊥ ﱞﱞB]
The SI unit of poynting vector S is Js^-1 m^-2 or Wm^-2.

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