Practice question · Multiple choice
The Doppler shift differs depending on whether the source or the observer is moving, even at the same relative speed. Why does the medium break the symmetry?
Hints
- Ask what the wave speed is measured relative to.
- Compare with light, where there is no medium and only relative speed matters.
Show the answer
C. Because the speed is fixed relative to the AIR, not the source
Why
A medium provides a preferred frame, so "who is moving" is a real question. For light there is no such frame and only relative velocity appears, which is precisely the puzzle special relativity resolved.
Practise Sound Waves and the Doppler Effect
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