Starting with the energy density of an electromagnetic field U = ε0E^2 /2 + B^2 /2µ0...

Starting with the energy density of an electromagnetic field U = ε0E^2 /2 + B^2 /2µ0 and using two of Maxwell equations in free space, show that the rate of change of U is equal to the divergence of the Poyinting vector S, taken with the opposite sign, that is dU/dt = −∇ ∙ S

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genius_generous answered 2 years ago

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