Rms Electric Field of a light bulb

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jmm5872
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Find the root-mean-square electric field (averaged over all frequencies) at a point in space 1 meter from a 40-watt light bulb.

The emitted power: P = 40 W
R = 1 m

Intensity: S = P/(4[tex]\pi[/tex]R2)

S = (c/4[tex]\pi[/tex])<E2>

Erms = (<E2>)1/2

Now I will set the two equal and solve for <E2>:

P/(4[tex]\pi[/tex]R2) = (c/4[tex]\pi[/tex])<E2>

Does this look correct? My main concern is with the part that says averaged over all frequencies.


(NOT SURE WHAT IS WRONG WITH THE LATEX, PI IS NOT SUPPOSED TO BE A SUPERSCRIPT!)
 
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