- #1
fluidistic
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I'm all mixed. I've read passively through a tiny part of Jackson's book on electrodynamics and some Hecht on Optics.
Why are copper and gold excellent conductors while iron conducts less considering that copper and gold absorb somehow greatly light in the visible spectra, particularly in wavelengths corresponding to blue/green and hence their color? Wouldn't that mean that copper and gold doesn't reflect as well light as iron, since they do absorb? And a not so good reflector should be a not so good conductor? Or I'm wrong?
Maybe I should considering the absorption over the whole EM spectra, not only visible and I'd see that copper and gold absorb less than iron. In other words, their emissivity would be less than the one of iron.
Doing a quick search (http://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html) I found out that indeed iron has a greater emissivity than copper and gold though it's hard to compare since surfaces aren't necessarily the same.
I'd like some clarifications.
Thanks.
Why are copper and gold excellent conductors while iron conducts less considering that copper and gold absorb somehow greatly light in the visible spectra, particularly in wavelengths corresponding to blue/green and hence their color? Wouldn't that mean that copper and gold doesn't reflect as well light as iron, since they do absorb? And a not so good reflector should be a not so good conductor? Or I'm wrong?
Maybe I should considering the absorption over the whole EM spectra, not only visible and I'd see that copper and gold absorb less than iron. In other words, their emissivity would be less than the one of iron.
Doing a quick search (http://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html) I found out that indeed iron has a greater emissivity than copper and gold though it's hard to compare since surfaces aren't necessarily the same.
I'd like some clarifications.
Thanks.