Drexel dragonThe Math ForumDonate to the Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.

Math Forum » Discussions » sci.math.* » sci.math.independent

Replies: 2   Last Post: Aug 15, 2014 11:02 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Pentcho Valev

Posts: 3,415
Registered: 12/13/04
Posted: Aug 15, 2014 2:52 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

University of Texas: "Thus, the moving observer sees a wave possessing the same wavelength (...) but a different frequency (...) to that seen by the stationary observer. This phenomenon is known as the Doppler effect."

That is, in accordance with the formula

(frequency) = (speed of light)/(wavelength),

the speed of light waves (relative to the observer) varies with the speed of the observer, in violation of Einstein's relativity.

Fang-Yuh Lo, Department of Physics, National Taiwan Normal University: "Observer moves toward source: frequency becomes higher. Observer moves away from source: frequency becomes lower. How much higher (lower)? Wavelength does not change. Change in velocity: Vnew=Vwave±Vobs. (...) Examples: sirens of a traveling vehicle; speed radar of police; red shift in light - astronomical observation."

That is, if the observer starts moving towards / away from the light source with (small) speed v, the speed of the light relative to him shifts from c to c'=c±v, and this shift causes the frequency measured by him to shift from f=c/L to f'=c'/L, where L is the wavelength:

"Doppler effect - when an observer moves towards a stationary source. ...the velocity of the wave relative to the observer is faster than that when it is still."

"Doppler effect - when an observer moves away from a stationary source. ...the velocity of the wave relative to the observer is slower than that when it is still."

Pentcho Valev

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.