So confused about reflection from metal surfaces

AI Thread Summary
The discussion centers on the confusion surrounding energy loss when electromagnetic (EM) waves interact with metal surfaces. It highlights that reflection involves both electric and magnetic fields, which induce currents and contribute to resistive losses in non-ideal conductors. The user seeks clarity on whether the energy loss from each field is similar, given their equal energy storage in the wave. Recommendations for further reading include a Wikipedia article on reflection mechanisms and insights into applications in fiber optic cables and telecommunications. The conversation underscores the complexity of reflection phenomena in physics.
H_man
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:bugeye:Hi All...

I am really confused about the mechanism of loss of energy when an EM wave hits a metal surface.

I always thought the reflection was due to the motion of the electrons in the metal (due to the electric field of the wave). Which suggests that resistive losses would come from the E field of the wave doing work.

However, I also know the magnetic field penetrates in the manner of the skin effect and also induces currents to cancel the changing B field.

So it seems to me that both field contribute to currents and hences losses in a non-ideal conductor.

The energy stored in each of the fields in the wave is equal so I would assume that the loss caused by each would similar?

Can anyone relieve my confusion :confused: Or even just tell me of a good textbook where this is treated. I've been looking but I can't find a clear answer.

I don't think looking at this from the view of individual photons is going to help :-(

Thanks in advance
Harry
 
Science news on Phys.org
Hi Harry..

have you read this:

http://en.wikipedia.org/wiki/Reflection_(physics)#Mechanisms_of_reflection
It's a good intro/overview.

See also further down that article on TYPES OF REFLECTION and SEE ALSO for further references...

And check this out for DIFFUSE REFLECTION...

Lot's going on with regard to reflections!

Also, I know this subject is VERY carefully engineered in fiber optic cable CLADDING...used at optical wavelengths...very high frequency...you might check on that and perhaps waveguides, such as those used in telecommunications to get broadband signals up to radio horn antennas...the one's you see on top of many towers around the US...
 
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