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norhh Nov13-12 01:11 AM

particle theory of light
 
If light is a particle then it should definitely make sonic booms.but i did not find them even by keeping my er on light.ok light value is high but even if these guys did mistake in calculations then also it is definitely greater 1000km/hr but i would not happen.even for x-rays holds ssame.and protons,electrons,neutrons.

Matterwave Nov13-12 01:32 AM

Re: particle theory of light
 
????

Sonic booms?

K^2 Nov13-12 03:49 AM

Re: particle theory of light
 
... He thinks individual photons traveling through air should generate sonic booms because speed of light is greater than speed of sound.


I don't think any particle beam would generate a sonic boom traveling through air at supersonic speeds. Seems to me like you need a fairly massive object for that. But I could be off.

In any case, light interacts with air as a wave. Keep in mind that all particles exhibit duality. They have wave-like properties and particle-like properties. Nothing is strictly one or the other. But different interactions can result in one or the other manifesting strongly. Wavelength of visible light being greater than size of molecules in air, and even greater than average distance between molecules, light will interact with air as a wave. Therefore, there are no particle-like collisions between photons and air molecules.

At sufficiently high energies, such as these of gamma radiation, photons will begin interacting with air in a more particle-like manner.

norhh Nov13-12 06:59 AM

Re: particle theory of light
 
Quote:

Quote by K^2 (Post 4157296)
... He thinks individual photons traveling through air should generate sonic booms because speed of light is greater than speed of sound.


I don't think any particle beam would generate a sonic boom traveling through air at supersonic speeds. Seems to me like you need a fairly massive object for that. But I could be off.

In any case, light interacts with air as a wave. Keep in mind that all particles exhibit duality. They have wave-like properties and particle-like properties. Nothing is strictly one or the other. But different interactions can result in one or the other manifesting strongly. Wavelength of visible light being greater than size of molecules in air, and even greater than average distance between molecules, light will interact with air as a wave. Therefore, there are no particle-like collisions between photons and air molecules.

At sufficiently high energies, such as these of gamma radiation, photons will begin interacting with air in a more particle-like manner.

Thanks i did not knew that thing i thought light is both a particle and wave.

mfb Nov13-12 09:56 AM

Re: particle theory of light
 
Quote:

i thought light is both a particle and wave.
That is true.

High-energetic charged particles in matter can produce the electromagnetic equivalent to a sonic boom: Cherenkov radiation
But that requires charged and very quick particles, light does not work.

ZapperZ Nov13-12 10:00 AM

Re: particle theory of light
 
Quote:

Quote by norhh (Post 4157396)
Thanks i did not knew that thing i thought light is both a particle and wave.

Actually, it may be neither.

You should start by reading the FAQ subforum in the General Physics forum, and in particular, this entry:

http://www.physicsforums.com/showthread.php?t=511178

Zz.


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