3
votes
2answers
94 views

Is there a way to create a flickering frequency to be dependent on speed of the person looking at it?

Is there a way to make a screen or a road sign flash at different rates, depending on the velocity of the observer looking at it? I would like to achieve a state where two observers going at ...
5
votes
3answers
148 views

How would I perceive a purple ball when traveling at relativistic speeds

I have a 'thought experiment' which I'd like to ask about. I was thinking what speed I would have to drive towards a crossing to see a red light as a green light - pretty easy, using the doppler ...
1
vote
1answer
214 views

Why does heterodyne laser Doppler vibrometry require a modulating frequency shift?

On the wikipedia article (and other texts such as Optical Inspections of Microsystems) for laser Doppler vibrometry, it states that a modulating frequency must be added such that the detector can ...