Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
At what speed would somone have to travel for the color yellow to appear green?
During a trip home, my father challenged me with the question "At what speed, in m/s, would someone have to travel for yellow to look green?" Since I am only in 9th grade high school physics, not even in AP yet, I was wondering what the answer was. I know my dad asked me jokingly, but now I am curious.
2 Answers
- Stratocaster1111Lv 51 decade agoFavorite Answer
Using the Doppler effect and Einsteins theory of relativity (since light travels so fast).
F = f(1 + v/c)
Where F = observed frequency, f = source frequency, v = speed, c = speed of light
The frequency of yellow light is approximately 520 THz
The frequency of green light is approximately 570 THz
Rearranging the equation for v:
v = 28800000m/s
or 9.6% the speed of light toward the yellow object
- ?Lv 61 decade ago
You have to be moving AWAY from the green light for it to look yellow at sufficiently high speeds because yellow light is of lower frequency. You will have to be receding from the green light at relativistic speeds for this to happen.
Define Green and Yellow by their wavelength and apply the relativistic Doppler Effect. From there you can calculate the necessary speed.
