Doppler effect of light problem Please assist

AI Thread Summary
The discussion revolves around a problem involving the Doppler effect of light as experienced by observers on Earth and on a spaceship traveling between Earth and Mars. Observers see the spaceship's headlights as green at 500 nm and taillights as red at 600 nm, prompting calculations for the speed of the spaceship relative to the speed of light (u0/C) and the frequency of the lights according to the pilot. The initial calculations suggest B = 1/11 and a wavelength of 456 nm, though there is uncertainty about this value due to the Doppler effect. The conversation highlights the need to clarify the relationship between wavelength and frequency, with a request for further assistance on the calculations. The thread emphasizes the complexities of applying the Doppler effect to light in a relativistic context.
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There is a space shuttle service between Earth and mars. Each spaceship is equipped with two identical lgihts one at the frotn and one at the rear. The spaceships travel at constnat speed u0 relative to Earth such that an observer standing on Earth sees the headlights of an approachin ship as green 500nm wavelength while the observer sees taillights of a departing ship from Earth as red with 600 nm wavelength.

What is the value of U0/C ? What is the frequency of the lgith from the either of the lights on a spaceship according to the pilot of that ship?

too ka lot of headracking but i figured

500 = f0 (root(1+B/1-B))

and 600 = f0 (root(1-B)/(1-B))

and B = 1/11 and wavelength is 456nm (not sure about this, since the ship is aproaching then the light approaching Earth would be more higher than what was really emitted fro mteh ship. so is 456 wrong??

part B)
One spaceship accelerates to new speed u relative to Earth such taht one taillight of the spaceship i nfront of it apears green of wavelength 500nm. What's he value of u/c?

this follows from the first part
the answer would be altered by the real frequency of the ship's headlight.

please help...
 
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As you've indicated in your first paragraph, wavelength is measured in nm.
However, frequency is not.

Check your system of equations again.
 
robphy said:
As you've indicated in your first paragraph, wavelength is measured in nm.
However, frequency is not.

Check your system of equations again.

thank you for pointing my typo

can yo help me with the question, however
 
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