Sunlight and Sound

How big is a partical of sunlight and what is a sound wave made of?

E/c^2=m <- There's the mass of a ray of light.

Sound is a pressure(p) wave so it's made of air molecules: mostly oxygen, nitorgen, etc.

Disclaimer: I have a physics degree so don't take anything I say seriously

Problem about light is, that it has the properties of a wave as much as of a particle (maybe a little more even). If it is viewed as an EM wave, than it should technically not have any dimensions or mass at all. However, there are cases where the particle model is the only one to explain a phenomenon, let alone the fact that you can measure (!) the 'mass' of light. Another problem is, that light particles only have a mass as long as they are in motion and their entire mass is relativistic. Thus, once it impacts somewhere, it transfers its energy to the other particle that in turn changes its energetic state sometimes emitting other EM waves of its own shortly. At that point, the initial light particle does no longer exist as such.

As for sound waves, they are, as described, shockwaves and thus only exist in some sort of medium. It doesn't have to be air at all, since every matter resonates with shockwaves. We use to hear sounds conducted through air and water, but even rocks do resonate with shockwaves and give them back and you can measure their sound wave with a seismometer very precisely, even if the air isn't thick enough to bring its whole amplitudes up to your ear so that your your senses are irritated.

And that is no high grade academic physics, I just picked up a few things at school.^^

This graph shows some info on 'how big' sunlight is;

All your answers are theories. Guesses, speculation about what we don't know.

I always found a fun question to ask (without simply googling the answer...) is "What is fire made of?"

But the above answers to your questions are correct to the best of my knowledge

The size of a particle of 'sun light' would be between 400 - 700 nanometers. That is the range of the visible spectrum of light. But the sun gives out many variants of that, such as UV as an example. But that is not 'sun light' essentially, because we cannot see it with our eyes

As much as everything, but Whyte Horse's answer is the most accurate one that we have.

Everyone is focuse on science and western style thought.

This is posted in the philosopyh section. Think philosophically.

Kalkho wrote: As much as everything, but Whyte Horse's answer is the most accurate one that we have.

With all due respect - this statement is false.

E/c^2=m is describing the mass of any energy particle, be it light or matter or whatever else I might be missing out while focusing on what we know best. Regardless of that it is the mass and not the size of them, it also is dependant on the energy the respective particle has. Thus, a faster particle is heavier than a slower one and light particles would by that formula have a relativistic mass of c/c^2=1/c which they would not even have if they were massive objects.

And, as stated before, a pressure wave doesn't need air to exist - any medium would do, so there is a slight incompleteness in that statement.

Adder wrote: This graph shows some info on 'how big' sunlight is;

Solar Radiation Spectrum

That, too, doesn't illustrate the magnitude of sunlight but only how many of what wavelength EM waves are being emitted by the sun.

Akkarin wrote: The size of a particle of 'sun light' would be between 400 - 700 nanometers.

In fact, that is approximately the spectrum of wavelengths that the human brain can interpret as light (which you said - granted). It is, however, not the size of light particles but the length of the light waves. With this and the formula f=λc where λ is the wavelength, you can see what light frequencies they are, respectively. And since E=hf, you can even figure, how much energy light of different frequencies has.

Akkarin wrote: But the sun gives out many variants of that, such as UV as an example. But that is not 'sun light' essentially, because we cannot see it with our eyes

The sun doesn't give you 'variants' of the same spectrum. It emits a certain broad spectrum of EM waves and only those within the visible wavelength range can be percieved and interpreted by humans. Also, that doesn't mean the other wavelengths are any less 'light'. They are just not visible to us, but by their physical properties and the way they interact with other energy types they are quite the same, even if they carry other amounts of energy.

Rickie The Grey wrote: All your answers are theories. Guesses, speculation about what we don't know.

Brave statement. For all I know the earth might as well be flat. All I have seen were images and people telling me differently, but it might still be wrong (and even a huge conspiracy) for all I know. However, the theories we have seem to make testible predictions about events that turn out to be correct, too. Thus, as much as they may be wrong (we could in fact be all living in a matrix, really) at the end of the day, they are at least comfortable and help us understand some things just enough to satisfy our curiosity - and you asked, thus you have it, too.

Rickie The Grey wrote: Everyone is focuse on science and western style thought.

This is posted in the philosopyh section. Think philosophically.

Oh... sorry
Next time you might want to specify what kind of answer you are searching for. Because even with that in mind I still don't know what you expect other than the answers you have. The questions don't suggest any different. But that may be just me.

[/random-ramble-'bout-science-stuff-'n-shit]

This is posted in the philosopyh section. Think philosophically. [/quote]Oh... sorry
Next time you might want to specify what kind of answer you are searching for. Because even with that in mind I still don't know what you expect other than the answers you have. The questions don't suggest any different. But that may be just me.

[/random-ramble-'bout-science-stuff-'n-shit][/quote]

Sorry I thought the subforum title was the key.

What kind of answers? It's the philosophy section I wouldn't dare try to direct how people should answer.

If this makes it easier, imagine you are living 4,000 years ago how would you answer these questions.

Thank you Gisteron, I needed the laugh! :woohoo:

How would I've answered if I lived 4000 years ago?...

Sunlight particles? Sound waves? OMFG you must be in some evil bond with Apophis! Heresy! Heresy! Its all magical and you know it! Did your slave mentor not teach you all that infallible wisdom?!

Enjoy! :D

You'd have answered on your iStone.

I am not refering to any one in particular, but let's make sure we all play nice.

I'm doing a course in 'sound' at the moment and they define sound as the experience of hearing pressure waves in the air, and not the actual pressure waves. Needless to say I got that exam answer wrong... they should have said noise is the phenomena and sound the experience or something because in society we use sound to mean err, sound/noise/pressure. So then I'd have to assume 'sound waves' to mean experiencing sound in patterns resembling waves.

Akkarin wrote: The size of a particle of 'sun light' would be between 400 - 700 nanometers. That is the range of the visible spectrum of light. But the sun gives out many variants of that, such as UV as an example. But that is not 'sun light' essentially, because we cannot see it with our eyes

How big is an iceberg - what you can see above water or what your ship smashes into unseen under the surface. Dont forget either that sunlight burns your skin and that is mostly in the UV range.

I understand though you dont get much sun in the UK

Gisteron wrote:

Adder wrote: This graph shows some info on 'how big' sunlight is;

Solar Radiation Spectrum

That, too, doesn't illustrate the magnitude of sunlight but only how many of what wavelength EM waves are being emitted by the sun.

Doesnt it? I thought the Y axis showed the magnitute, versus the X axis showing the wavelength. I knew it wasnt answering the question though and its why I said "This graph shows some info".

The original question is in a form which is not in line with scientific understanding about the nature of light, so people posting different parts of the puzzle might in part help answer whatever is being asked by the question. I think its better to try and answer and miss the mark slightly then not answer at all.... or worse pick on people trying to answer (no-one in particular, just thinking out loud).

I dont see the philosophical question on how big is a 'particle' of sunlight. Can you rephrase?

Keep thinking.

Try using images and not words.

Use terms of wonder and not science.

OK, my answer is between 10 and 14 hours;

oh you want philosophy... well quantum mechanics states that light is both a wave and particle whose position and energy cannot be known simultaneously. The size of a photon is a probability distribution across both space and time.

Furthermore, guage theory says that a photon is the Abelian U(1) symmetry of a complex number, which reflects the ability to vary the phase of a complex number without affecting observables or real valued functions made from it, such as the energy or the Lagrangian.

Rickie The Grey wrote: Use terms of wonder and not science.

In fairness the words behind the explanation are both

Adder wrote:

Gisteron wrote:

Adder wrote: This graph shows some info on 'how big' sunlight is;

Solar Radiation Spectrum

That, too, doesn't illustrate the magnitude of sunlight but only how many of what wavelength EM waves are being emitted by the sun.

Doesnt it? I thought the Y axis showed the magnitute, versus the X axis showing the wavelength. I knew it wasnt answering the question though and its why I said "This graph shows some info".

Yes, true. Shouldn't have phrased my critique like that; I apologize. I just meant that the question about the actual dimensions of sunlight particles isn't being answered (I'm not even sure it is known). The diagram displays the amount of energy transfered on different EM frequencies and not the size of any of them. So yes, the light 'magnitude' or - to phrase it correctly - the light 'flux' (not sure it is even the same as 'intensity', as I'd think tha the intensity is the wave amplitude; but then again - there is somewhere around no relevance at all that wave amplitude has to the physical interaction of light to other things) is in fact displayed. The 'size' of the particular waves or particles (depending on the understanding of light that is being applied) is not..