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Show that the avearge energy density of the electric field `vecE` equals the average energy density of the magnetic field `vecB`, in electromagnetic waves.

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`mu_e=1/2e_0E^2 & u_B=1/2 B^2/mu_0`
`mu_E=1/2E_0E^2=1/2 e_0(CB)^2 As c=E/B`
`=1/2 e_0 B^2/(mu_0e_0) c=1/sqrt(mu_0E_0)`
`=B^2/(2mu_0)`
`mu_B`
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CBSE COMPLEMENTARY MATERIAL-ELECTROMAGNETIC WAVES AND OPTICS-SHORT ANSWER QUESTION 2 MARKS
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