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How does it interact with the magnetic and electric fields of the radio waves while receiving them?
If you put a conductor parallel to the direction of the electric field
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I cannot see multiple ways to interpret that line, can you show me some?
what light ??Well the direction of the electric field is at a right angle to the direction the light would be going. ......
what light ??
we are talking about radio wave E-M field
Dave
What do you mean by "over" or "under" the electric field? In planar waves (or waves similar to them), the electric field is the same everywhere in the plane perpendicular to the propagation direction of the wave.
try the ARRL Radio Handbook
it gives a very good background to radio transmission and reception including antenna theory
cheers
Dave
Parallel
As examples:
If the polarization of light is vertical, the electric field is vertical, and your antenna has to be vertical to pick up the signal (at least with some vertical component).
With a circular polarization, the electric field is vertical->horizontal->vertical->..., and your antenna direction does not matter unless it is orthogonal to the direction of propagation of the wave (or has some orthogonal component).
Even with the antenna and the electric field being at 90 degrees to each other there will still be some signal induced into the antenna .... just not very efficiently
In the field, in pratical situations, we see a 25 to 30 dB difference in signal strength when the polarisation is out by 90 deg
Dave
I think you have something like that in mind. Forget it. Light does not work that way. That is not a 3-dimensional picture! Imagine those fields everywhere in the (z,y)-plane, and it gets better. While it is possible to emit directed electromagnetic waves, you cannot really "miss" an antenna in the way you imagine it.So if the antenna is vertical and the electric field is vertical and the photon moves by the antenna but is a bit too far left to hit it directly, could the magnetic field induce current in the antenna?
Photons are not like little bullets and they don't "meet and antenna" in the conventional sense. It is really not helpful to look at it this way. How could you even start to consider how this single photon (dimensions / extent totally unspecified) will interact with a piece of metal, which consists of a distribution of charges all over it? Stick to waves if you want to understand most non-QM phenomena. There is nothing wrong with ( you are not making any compromises) using the wave approach.If the polarization of the signal is vertical and the photon meets the vertical antenna straight on, will that generate the most current? I hope this has to do with dipole antennas.
Photons are not like little bullets and they don't "meet and antenna" in the conventional sense. It is really not helpful to look at it this way. How could you even start to consider how this single photon (dimensions / extent totally unspecified) will interact with a piece of metal, which consists of a distribution of charges all over it? Stick to waves if you want to understand most non-QM phenomena. There is nothing wrong with ( you are not making any compromises) using the wave approach.
When a photon gets absorbed by an atom or (presumably) an antenna, it does something. When a photon "goes through" or "past" an atom or antenna, nothing happens. Photons interact destructively, in an "all or nothing" fashion.When a radio photon goes through an antenna it induces current.
When a photon gets absorbed by an atom or (presumably) an antenna, it does something. When a photon "goes through" or "past" an atom or antenna, nothing happens. Photons interact destructively, in an "all or nothing" fashion.
I think you have something like that in mind. Forget it. Light does not work that way. That is not a 3-dimensional picture! Imagine those fields everywhere in the (z,y)-plane, and it gets better. While it is possible to emit directed electromagnetic waves, you cannot really "miss" an antenna in the way you imagine it.
This is just not an accepted model. I can't think where you would have read it. To get into this subject you really have to ditch conventional ideas. Photons can be treated as particles under some circumstances - the appear to transfer momentum to a particle with mass, for instance - but when you say "surrounding the photon" you are implying that it has a size (for it to be surrounded). You can lay that one to rest for yourself if you ask yourself just what 'size' a photon could have. Is it related to the wavelength of the particular radiation? That would make it in the order of kilometers in extent for an LF radio signal. How would something of that size be expected to interact with a tiny whip antenna (10cm) that you could find on a hand held receiver? The 'size' thing just gets you going round and round in circles and leads you nowhere. Just stick to the universally accepted idea that a photon is an amount of energy which is transferred when EM energy is emitted or absorbed by a 'system'.The EM fields surrounding the photon induce the current, right? That's what I meant. Once again I'm a beginner and don't really know much about this subject. Thanks for the help!