Doppler Shift of a Yellow Light?

Ha

Interesting speculation

1. The light will not change color no matter how fast you go. Only in your perception it will, so unless the law enforcement is traveling within your frame of reference you would be found guilty anyway.

2. True, if you are moving towards the light its frequency will increase towards the blue and will appear green to you, but the acceleration would kill you.

3. If you could travel with speed of light why would you care about traffic lights?

Good question anyway.

light coming toward us shifts to red, while light leaving us shifts to blue. you'd have to drive backwards at the yellow light until it shifts to green, then drive forward. but that will in turn make the light red again one you get close enough. you're forever stuck at the light. just wait it out, dude.

It depends on what your interpretation of yellow and green are. Many traffic lights now use LED lamps - so

For example:

This Green LED is centered at 518nM

http://www.rohm.com/products/databook/led/pdf/slr3...

This yellow one at 591nM

http://www.rohm.com/products/databook/led/pdf/sli-...

So the speedup would be such that 591/c = 518/(c-speed)

i.e. speed = c*(591-518)/591 = ~12.3% of the speed of light.

you got it backwards, digdug. Light shifts towards blue when you accelerate towards it.

145,000 mph.

If you hear some deep-toned cyclical sounds behind you... that's the police siren.