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FrozenGate by Avery

Doppler effect with light

pullbangdead said:
Doppler effect with light waves happens, and gets used in the real world everyday all across the world.  Police use radar guns to measure speed of moving objects, baseball scouts use radar guns to measure the speed of pitches, people use radar guns to measure the speeds of things all the time.  Radar guns use radio waves and the Doppler effect, measuring the shift of the radio waves after they bounce off of objects to calculate the speed.  This is radio waves, but it's still exactly the same thing as visible light, just a longer wavelength.
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So with visible waves, they still have to bounce off of something so as to shift the wavelength?
 





^No. If a moving object is emitting light on its own, there will be Doppler effect with the light it is emitting. But cars generally aren't emitting any electromagnetic radiation that can be measured in such a way, so the radar gun bounces some off of the car to measure its speed. Whether galaxies are moving towards or away from us, for instance, can be deduced by blue-shift and red-shift, and you can deduce the speed by the amount of Doppler effect seen if you know what the wavelength of the light would be if the object was stationary.
 
Thanks. But why does light shift then? :S Don't light waves act the same as radio waves in doppler effect?
 
asntronomers prove the big bang theory with the doppler effect. or more known as red shift in this case. as the astronomical body moves away is shifts away from red.

im interested if different wavelengths travel different speeds?

moving away - redshift
toward - blue shift
 

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caleb said:
im interested if different wavelengths travel different speeds?
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This is an interesting question. In any medium the answer is yes, different wavelengths do travel different speeds. That is why a prism is able to separate colors from white light because they travel at different speeds. You get this information from the dispersion relation which is concerned with the propagation speed with relation to frequency and wavelength.

In vacuum the relation is

frequency = speed of light / wavlength

so all wavelength should travel the same in vacuum. Of course that relation is derived by assuming there is nothing to interact with, but if there is some wierd quantum gravity or something that does affect it then that relation is not really true. There is currently a new gamma ray telescope that is going to see if the above relation is true by measuring the frequency of gammas and see if they all get there at the same time or if there is a frequency chirp (the frequency goes from low to high or high to low) in terms of their arrival time.
 
Light is way slower if U open Ur EYES & see the hiden seemingly instantanious actions.

Gonna guess its 9 dimentions or 10.
 
Laserrod said:
Light is way slower if U open Ur EYES & see the hiden seemingly instantanious actions.

Gonna guess its 9 dimentions or 10.
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WAT?


wat.jpg
 
Better, WUT is for:

lolwut.jpg





Good, my young padawan. :)




Now, KILL HIM.






But i can't! it's not the jedi way





You want revenge, KILL.....HIM.






Hmm.....ok :D *SCHHHHHHHHHSSSHHHHHHHHHUUUUUUNNNNN*








:D:D REJOICE [smiley=2vrolijk_08.gif] [smiley=2vrolijk_08.gif]
 
nikokapo said:
[quote author=Laserrod link=1214677024/12#21 date=1215149437]Light is way slower if U open Ur EYES & see the hiden seemingly instantanious actions.

Gonna guess its 9 dimentions or 10.
Click to expand...

WAT?


wat.jpg
[/quote]

U just porned my statement . Shame on U. Bad words. Their are young children reading here.

In my defence lookup/Google photon entanglement Photon pairs.
 
Does anyone know what the aircraft design changes invented were stop the sonic booms as aircraft pass through the sound speed barrier?

I read they figured out how to stop the sonic booms.
 
Right ..... did you know that when you crack a whip its actually the end of the whip breaking the sound speed barrier :D
 
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