2. Physics question. There's a rotating exhaust vent which is very shiny, highly reflective. At night it seems to have a prismatic effect as it takes yellow and white street light light and generates a rainbow of colors -- mainly we see glints of red and blue along with white. Is there an explanation for that effect?
I came here to illuminate you about the above thread, but this intrigues me. I'm guessing that whatever is being exhausted from the vent is causing some refraction from the light bouncing off the reflective surface - resulting in the effect. But it's a wild swing in the dark, to be honest.
This sounds like the effect from a diffraction grating (a finely ruled shiny surface). The diffraction gratings used in spectroscopy have parallel grooves etched in the surface that reflect and disperse light into its constituent wavelengths.
It does, but I'm assuming a vent doesn't have the kinds of gaps that are that narrow.
Refraction is when waves, whether physical or electromagnetic, are deflected when the waves go through a substance.
I assume that something is being vented - possibly water vapour/steam - thus the possibility of a 'rainbow' effect.