i have a question, but i dont write good english.
i hope you could understand me.

Light is electromagnetic wave, so if i make a emmiter at (for exemple ) red frequency, does the antenna radiate light (red) ?

if yes what quality does the light have ?

thank you

right, im not a physicist, but ill try to answer some



Light is electromagnetic wave, so if i make a emmiter at (for exemple ) red frequency, does the antenna radiate light (red) ?
sure, why wouldnt it be red?

what antenna are you talking about by the way?



if yes what quality does the light have ?

well it would look red :)

other than that, it would have a wavelength of 650 to 800 nanometers as seen in the following picture
http://www.dnr.sc.gov/ael/personals/pjpb/lecture/spectrum.gif
also, velocity of a wave = frequency * wavelength

in all electromagnetic waves, the velocity is the speed of light

so the frequency of the red wave will be
wavelength/c
where c is the speed of light

no matter the kind of antenna and the color of light, it's just an exemple.

my question is :
is possible to radiate light by a (radio) emitter which have the frequency of light ?

What quality have the light ?

it's monoplanar, or just a beam?

thanks

i have a question, but i dont write good english.
i hope you could understand me.

Light is electromagnetic wave, so if i make a emmiter at (for exemple ) red frequency, does the antenna radiate light (red) ?

if yes what quality does the light have ?

thank you

It's called a red LED.

http://upload.wikimedia.org/wikipedia/commons/e/e9/Red_led_x5.jpg

no matter the kind of antenna and the color of light, it's just an exemple.

my question is :
is possible to radiate light by a (radio) emitter which have the frequency of light ?

What quality have the light ?

it's monoplanar, or just a beam?

thanks

No, a radio wave transmitter cannot emit visible light.

you would need something vibrating really fast to produce the light wavelength, right? like a filament. in the radio's case the crystal would have to do it, probably just making a glowing crystal, if it could be done.

it' s a theory !

if i make a (radio) transmitter at the frequency of light can it radiate light ?

It's called a red LED.

http://upload.wikimedia.org/wikipedia/commons/e/e9/Red_led_x5.jpg



No, a radio wave transmitter cannot emit visible light.


why?

radio emitter emit electromagnetic wave no ?
so if it can emit at the frequency of visible light, why it can't emit visible light ?

why?

radio emitter emit electromagnetic wave no ?
so if it can emit at the frequency of visible light, why it can't emit visible light ?

a red light emit visible light by heating a filament.

it's not what i mean.

What emits radio waves? You're talking about the radio antenna emitting a band of the electromagnetic spectrum that it wasn't designed to produce. There are different methods to making different types of waves. It just so happens electrons being squeezed through a tiny filament produce the band of light we can see, and a lot of heat.

pretty much. radio antennae produce radio waves, which havent nearly got enough energy to create visible light, or even the heat of infrared for that matter

sorry for my english !
i can't explain it , but i try one time.

if i make a emitter, as a radio emitter but with a frequency of light.

it's a theory, i can't make it.

and if i attach a antenna as a radio antenna, but an antenna for the light frequency.

What happend, does the emitter emit light (as a radio emmiter emit radio electromagnetic wave), this emiter will emit electromagnetic wave at frequency of light = light ?

No matter the energy and the making of this emiter, it's just a theory.

thank you for your patience :p

if i make a emitter, as a radio emitter but with a frequency of light.

it's a theory, i can't make it.

and if i attach a antenna as a radio antenna, but an antenna for the light frequency.


It's just a matter of semantics - an emitter at a frequency of light is, by definition, not a "radio emitter" because it does not emit radio waves! And yes, if you could construct an antenna with a resonant frequency of 4.3x10^14 Hz it would emit red light.

thank you for your response

i make another post with another question about light, but no response.

perhaps you know ?

light is electromagnetic wave.

so if i generate a electromagnetic wave, it's be absorb by a metalic plate who is link to earth (masse/ground) and it's be bounce by the same metalic plate who is not link to earth.

and the light ?

why a metalic plate who is link to ground bounce the light ?

sorry for my poor english, hope you understand me

thank you

oh..should this be related to the old argument , is light awave or a particle.

no i know the duality of the light.
it's not the purpose.

i would like a explication.

so if i generate a electromagnetic wave, it's be absorb by a metalic plate who is link to earth (masse/ground) and it's be bounce by the same metalic plate who is not link to earth.

and the light ?

why a metalic plate who is link to ground bounce the light ?

You can't emit radio waves tuned to the frequency of red light. I don't suppose you mean powering a red LED with a carrier signal from a radio transmitter. In that case the red light would flicker in accordance with the radio wave oscillation.

why a metalic plate who is link to ground bounce the light ?

Did you mean:

Why does a metal plate that is grounded reflect light?

yes

thank you for your translating:)

Why does a metal plate that is grounded reflect light?

and the same metal plate that is grouned doesn't reflect radio wave ?

thank you

I think the answer to both of your questions can be explained by the significantly difference properties of electromagnetic waves at various frequencies. Although radio waves and visible light are, indeed, both EM waves, radio operates at a frequency of around 10^5 Hz, while light is centered around 10^14 Hz.

You can see, then, that light waves vibrate about 1,000,000,000 (one billion) times faster than radio waves. The average light wavelength is also 1 billion times shorter, and this has major consequences for how such waves interact with matter.

So, although you could in theory create a radio/antenna system that emits visible light, it can't be done in practical terms because the electronics and materials used in conventional radio equipment is not capable of operating at such extremely high frequencies/short wavelengths. We have to use a total different type of apparatus to do that (i.e. lasers or radiant heat sources light a light bulb).

This is also part of the reason why a grounded metal plate will generally reflect (instead of absorb/conduct) visible light. At light frequencies, the reflection, refraction, and absorbtion of EM waves is determined primarily by the refractive indices of the two materials at the boundary layer. Most of the photons in this situation are not converted directly into electrons (although if they were, they would then flow to ground, as you're thinking). Look up the photoelectric effect on Wikipedia for some insight as to what's going on in this type of situation.

thank you for your response
:)

i make a dream :D

(make a emp with the lightning.)

it's a theory, but i think it's possible.

you have to make a Lightning rod, but

a coil Lightning rod .

A coil antenna who is as a Lightning rod. The Lightning make the coil antenna radiate the very powerful emp, due to lighting power.

what do you think about it, any comment welcome !

i make a dream :D

(make a emp with the lightning.)

it's a theory, but i think it's possible.

you have to make a Lightning rod, but

a coil Lightning rod .

A coil antenna who is as a Lightning rod. The Lightning make the coil antenna radiate the very powerful emp, due to lighting power.

what do you think about it, any comment welcome !

Brilliant!

you think it can work ?