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Here's a doppler question.
I always thought motion was relative. Why is it if the source
emits a 440 hz and it moves towards the observer at 30 m/s, the
observer hears 482 hz.(c=3D345). But if the observer moves
towards a 440 hz sound source at 30 m/s, the observer hears 478
hz. Why are these two heard frequencies different? In both
questions the observer and the source are approaching each
other. What *conceptually* is going on here?
-tony
-- =
Tony Wayne Those that can, do,
wayne@pen.k12.va.us -those that understand, teac=
<
Tony,
Great signature, if I quote it, whom do I attribute it to? You?
For light there is no aether - no universal standard of rest,
so the two corresponding formulas for the Doppler shift of =
light are indeed identical, but for sound there is an "aether",
it's the medium. From the perspective of the late 20th century =
our intuition is inverted. The aether was invented based on =
an understanding of the Doppler shift of sound. But now =
"relativity" is in the air and sound is not (no pun intended). =
Cheers,
Bill (13 out of 13 exams written, 5 given, 3 corrected) Larson
Geneva