Chronology | Current Month | Current Thread | Current Date |
[Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |
...suppose you shine red light (say, 680 nm) from
air into water. Since n = 1.33, both the velocity and wavelength will
decrease by this factor. Thus, (680 nm)/1.33 = 511 nm. This is the
wavelength of green light! We've probably all done this demo with a red
laser, and the beam remains red.
So color depends on frequency. In class I
usually say that color depends on wavelength. Lasers are rated by their
wavelength. Instead, should lasers -- like tuning forks -- be rated by
their frequency since this quantity never changes?