Hey, I just wanted to let you guys know that the equation you are showing as the model for the blue shift/red shift is the classical model. It works for sound waves, but not for electromagnetic waves. You have to account for the special theory of relativity.
The doppler effect for light needs to be modeled with:
Fr- Frequency received Fs- Source frequency C - speed of light V - velocity (either approaching the receiver or moving away)
Fr=[((C-v)/(C+V))^1/2)]*Fs
This is only for a receiver remaining still
But when v is positive the source is moving directly away from the reviver and fr is always less that fs: when v is negative, the source is moving directly toward the receiver and fr is greater that fs.
The effect is the same for sound the the quantitative relationship is different.
Anyway.... I'm just a student, so you should check it out yourself, but I was cruising the ole internet and noticed that.
Hope this helps
Make sure and check this out first b4 you publish anything, I'm no physics professor. But I do know that you modeled it using the same equation for sound Doppler effect, and light acts differently because it doesn't require a median for travel and well... light is crazy.... You know that Light is a mad crazy concept. Duality still bothers us, so ya.... Anyway I might be procrastinating So I'm just gonna end this now.
Email me for any clarification of my rambles....
Joseph - USA
19653
Answer
Thanks for your feedback. It is good that you are alert and looking deeper into things.
It is true that the equations given in "Doppler Effect Equations for Light" lesson at: http://www.school-for-champions.com/science/light_doppler_equations.htm are for the the classical model. Note that I have a condition that c >> v (the speed of light is much greater than the velocity of the object). In such a case, the equations hold or are a sufficient approximation.
The equations work fine for the Doppler radar used by police and in weather prediction. In astronomical measurements, the relativistic equations start to become more accurate.
Right now, I don't have a section on relativity, but I plan to get one up soon, and that will have the Doppler equations, taking relativity into consideration.
Do you have any questions, comments, or opinions on this subject? If so,
send
an email with your feedback. We will try to get back to you as soon as possible.
Feel free to establish a link from your website to pages in this site.
