The rms value of the electric field of the light coming from the sun is 720 N C^(-1). The average total energy density of the electromagnetic wave is

The rms value of the electric field of the light coming from the sun i

1.	The rms value of the electric field of the light coming from the sun is 720 N C^(-1). The average total energy density of the electromagnetic wave is
Answer» `3.3xx10^(-3) J m^(-3)` `4.58 XX 10^(-6) J m^(-3)` `6.37xx10^(-9) J m^(-3)` `81.35xx10^(-12) J m^(-3)` SOLUTION :Total average energy density of electromagnetic wave is `lt u gt = 1/2 epsilon_0 E_(rms)^2 + 1/(2mu_0) B_"rms"^2` `=1/2 epsilon_0 E_(rms)^2 + 1/(2mu_0) (E_"rms"^2/c^2) "" (because B_"rms"=E_"rms"/c)` `=1/2epsilon_0 E_(rms)^2 + 1/(2mu_0) E_(rms)^2 epsilon_0mu_0 "" (because c=1/sqrt(mu_0epsilon_0))` `=1/2 epsilon_0E_(rms)^2 +1/2epsilon_0E_(rms)^2 = epsilon_0E_(rms)^2` `=(8.85xx10^(-12))xx(720)^2 = 4.58xx10^(-6) J m^(-3)`

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The rms value of the electric field of the light coming from the sun is 720 N C^(-1). The average total energy density of the electromagnetic wave is

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