(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hi, here is the problem I'm having trouble with:

The rms value of the magnitude of the magnetic field in an electromagnetic wave is Brms = 0.137 T. The intensity of this wave is approximately...

2. Relevant equations

E = cB

I = (E_{rms}B_{rms}) / [itex]\mu[/itex]_{0}

3. The attempt at a solution

E = (3 x 10^{8})(0.137 T) = 4.11 x 10^{7}V/m

I = ((4.11 x 10^{7}V/m)(0.137 T)) / (4[itex]\pi[/itex] x 10^{-7}) = 4.47 x 10^{12}W/m^{2}

I keep re-doing this problem and I keep coming up with that same answer, but it is not one of the answer choices. Can anyone give me a clue as to what I'm doing wrong? Thanks, I appreciate it.

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# Homework Help: Intensity of an electromagnetic wave, given only rms value of magnetic field

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