Planar driven by light ?

[geraldfryjr]

Yep, My point exactly!!!!


"But my question to him is how would you transfer the force of the photons beating against each other to excite the molecules of the air in the same fashion."

"If light is a electromagnetic wave than how do you excite the air without a physical means."

"The only other way I know how to do this is to use Heat or Plasma."

"Light is at one frequency range and if the resonate frequency of the oxygen and nitrogen in the air is in this range it may be possible to do so but it would require a lot of power just to jiggle a few molecules."

"And you have to have a lot of displacement to make some decent SPL's to be practical."

[john65b]

I remember my classes in Quantum Physics 27 years ago...really black art stuff that was so over my head it made my head spin....I also remember trying to explain antimatter to my Computer Science roommate while "Under the Influence"...it always made it a little more explainable and believable...

And also etched in my memory is explaining the relativity analogy of "Einstein running into a barn with a pole longer than the barn at the speed of light - there would be a time period that the entire pole would be able to fit into that barn"...

And don't get me started on Schrodinger....

[monkish54]

Originally Posted by john65b

I also remember trying to explain antimatter to my Computer Science roommate while "Under the Influence"

I wish the friends I get "Under the Influence" with would ask me about antimatter!! Your friends are cooler than mine! LOL

[oshifis]

See Radiation pressure - Wikipedia, the free encyclopedia

[capslock]

Well, there is those little mills in glass bulbs that have aluminum foil that is blackened on one side. They turn when exposed to light. My understaning is that is down to the back side heating up more rather than photon momentum.

If you were to build a loudspeaker membrane to the same princible, it would likely not be suitable as a tweeter.

SEdwards, I am a PhD physicist and make a good living, as do many of my colleagues. The trick is to know when to get out of the tenure track and take an industry job. It is the general problem solving skills that many companies are after, not the specifics of any particular field of physics.

Edit:
The thermal explanation is correct: http://en.wikipedia.org/wiki/Crookes_radiometer

These things only work in a moderate vacuum, not at atmospheric pressure nor in high vacuum because you need a certain average path length for the gas molecules -- not the ideal conditions for a tweeter!

[SEdwards]

Just going off topic for a moment - what kind of physics do you specialize in capslock? I'm writing up my thesis to submit in January and starting to look at post doc applications with a sour face. I'm seriously thinking of jumping ship back to Australia.

[torroid88]

Perhaps crossed laser beams - if powerful enough could be modulated and aimed to cross in some small area and combined be powerful enough to excite the air to become a plasma that would fluctuate with the audio ? Withoug a diaphragm ! Sounds sort of like an ionic loudspeaker and the plasma would probably produce ozone - a no no !!! ... Back to the drawing board ...

[lduarte1973]

Originally Posted by torroid88

would probably produce ozone - a no no !!! ... Back to the drawing board ...

or it would blow up in smoke