Wavelength and energy questions.

Re: Wavelength and energy questions.


They are all the same in that they are radiowaves. The "differences" are in the wavelengths of those waves.



In a similar fashion. In a light bulb, electricity passes through a high resistance filament which heats up and glows throwing off photons. Different materials can be used in the filaments to make the bulb give off slightly different colors of light.

Radiowaves are magnetic flux. Every time electricty flows through a conductor a magnetic field is created. The frequency of the flux (measured in Hz.) is determined by the frequency of the electric current applied to the conductor. The strength of the magnetic field is determined by the amount of current flowing through the conductor. By "tuning" a receiver to the same frequency we can pick up that resulting flux.

This is very, very basic and there are a lot of other considerations that go into the overall process.



The "whole spectrum" would run from 0Hz to infinity so, while it is possible in theory, it isn't practical (or cost effective). Instead we build different devices to use specific ranges of the frequency spectrum.

so they are basically ripples caused by electrons moving?

That's about as basic as it gets, yes... lol

Thanks fishin

All electromagnetic radiation from 0 Hz to whatever frequency you like is all made of the same thing : photons.

When I was first learning about radar I asked this question :

I have an antenna that emits RF radiation, if I turn up the frequency of my generator enough will the antenna begin to emit light ?

The bottom line is that yes, it will.
The problem is that an antenna such as the one you have on your car isn't very good at converting electricity into light so while it would be emitting light at the appropriate frequency it would be doing so amazingly inefficiently and it would be hard to detect assuming you could detect it at all.
This is why the design of antennas change as you increase in frequency. It's to make them efficient at emitting and receiving the radiation of the appropriate frequency.

Assume you have a magic antenna on your car that is efficient at all frequencies.
Then you could turn up the frequency of your input generator and the antenna would emit radio waves, then microwaves through infra-red to green and through the violet and on into the ultraviolet continuing on into x-rays and gamma radiation.
You would see it get hot and then start glowing red and then green then blue and in a short time you'd have a splendid suntan because of the invisible ultraviolet being emitted.
Then you'd be in trouble because of the x-rays and gamma radiation destroying your DNA.
So best you keep your magic antenna in a sturdy box.

VERY INFORMATIVE. so when people say people say the speed of light they actually mean the speed of a photon in a perfect vacum that makes sense...

Yes.
The speed of light is the speed of a photon in a perfect vacuum.

The speed of light changes according to what medium you are in.
For example, the speed of light in water is much lower than in a vacuum so it is possible for a particle to travel faster than light in that medium. When they do you get Cerenkov radiation.