Electrical current when circuit is off

[Wotname]

Originally Posted by team karst

Correct. An e-field cannot exist inside a conductor. The more conductive the shield, the better the shielding effectiveness.

So there is no e-field inside a waveguide?

[team karst]

Originally Posted by Wotname

So there is no e-field inside a waveguide?

I should add clarity to my choice of words. Inside I meant to describe “within the conductor”. Ie. Inside the metal.
Typing on hh devices enables too many shortcuts [emoji30]

[team karst]

Originally Posted by team karst

I should add clarity to my choice of words. Inside I meant to describe “within the conductor”. Ie. Inside the metal.
Typing on hh devices enables too many shortcuts [emoji30]

Since E fields are quantified by Volts/meter; a Voltage gradient cannot exist inside good conductors.

[Dieseldude]

Originally Posted by Wotname

So there is no e-field inside a waveguide?

Wave guides work because of the fact that electrical charge tends to exist on the surface of a conductor. The is called the "skin effect". The higher the frequency of an AC wave form, the more pronounced is the skin effect. For microwave frequency, this makes hollow conductors, or wave guides an efficient means of propagation. The signal is propagated inside the hollow tube. So the complete electromagnetic field does in fact exist inside a wave guide when generated at a source that is coupled to the wave guide. That is what might not be understood by those who are unfamiliar. The source must be coupled to an end of the wave guide. Of course wave guide dimensions are chosen according to the wave length of the signal, which is a function of the frequency.


λ = C/f
Where,
λ (Lambda) = Wavelength in meters
c = Speed of Light (299,792,458 m/s)
f = Frequency



For microwave engineering, there are other formulae for establishing dimensions, but this is the fundamental frequency to wave length formula.