Ronn! wrote:> > (...) leaving a gash (...) (for Alberto: 21 cm, or 1420 megaHertz)
Alberto replied:> Uh? Hertz is not a unit of distance
Dan responded:It is in those convenient units where c=1. ;-)
Or perhaps he's referring to something like this: http://www.lucytune.com/academic/freq_to_wave.html
I do point out in class (I think I originally read it in an essay by Isaac Asimov) the fact that the frequency of the most extreme violet light humans can see is just about twice that of the most extreme red light we can see, which is the same relationship between the frequencies of, say middle C (256 Hz) and high C (512 Hz), so one could make the analogy that the width of the visible part of the electromagnetic spectrum is one octave, then note that while a piano keyboard spans 7 1/2 octaves, the frequency of detectable electromagnetic radiation as shown in that diagram covers something like 100 octaves or more . . .
-- Ronn! :)
Ronn Blankenship Instructor of Astronomy/Planetary Science University of Montevallo Montevallo, AL
Disclaimer: Unless specifically stated otherwise, any opinions contained herein are the personal opinions of the author and do not represent the official position of the University of Montevallo.
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