Rms Electric Field of a light bulb

AI Thread Summary
To find the root-mean-square electric field at a point 1 meter from a 40-watt light bulb, the intensity is calculated using the formula S = P/(4πR²), resulting in S = (c/4π)<E²>. The user expresses concern about correctly averaging over all frequencies in the calculation. The equations appear to be set up correctly, but clarification is needed regarding the averaging process. The discussion emphasizes the importance of ensuring the calculations align with the intended frequency averaging method.
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\piR2)

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

Erms = (<E2>)1/2

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

P/(4\piR2) = (c/4\pi)<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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