Hello,(adsbygoogle = window.adsbygoogle || []).push({});

The energy density of an electromagnetic wave is [itex]ε_{0}E^{2}[/itex]. To calculate the energy flux, at least in the derivation's I've seen, people just multiply by the speed of the wave, i.e., c. But doesn't this assume that the energy density is constant at all points?; but E changes periodically! Why isn't it then the integral of the energy density in the corresponding volume, so it would give something close to a half of the usual answer i see!?

Thanks in advance

**Physics Forums - The Fusion of Science and Community**

# Energy flux of an EM wave

Know someone interested in this topic? Share a link to this question via email,
Google+,
Twitter, or
Facebook

Have something to add?

- Similar discussions for: Energy flux of an EM wave

Loading...

**Physics Forums - The Fusion of Science and Community**