Tagged Questions
5
votes
2answers
81 views
In terms of the Doppler effect, what happens when the source is moving faster than the wave?
I'm just trying to understand this problem from a qualitative perspective. The Doppler effect is commonly explained in terms of how a siren sounds higher in pitch as it is approaching a particular ...
0
votes
2answers
74 views
Independence of frequency in sound waves?
Why does the frequency of sound wave depend only on the source? Why is the frequency and not any other "quality" independent of everything but the source?
And that said, why is velocity and ...
5
votes
1answer
210 views
Meaning of negative frequency of sound wave
Suppose that Alice and Bob are both holding speakers emitting sound at a frequency $f$. Alice is stationary while Bob is moving towards Alice at twice the speed of sound.
In the case of Alice, if I ...
0
votes
3answers
249 views
Doppler effect “apparent frequency”
In discussing Doppler effect, we use the word "apparent frequency". Does it mean that the frequency of the sound is still that of the source and it is some physiological phenomenon in the listener's ...
4
votes
5answers
498 views
Sound frequency of dropping bomb
Everyone has seen cartoons of bombs being dropped, accompanied by a whistling sound as they drop. This sound gets lower in frequency as the bomb nears the ground.
I've been lucky enough to not be ...
8
votes
1answer
319 views
Hearing a sound backwards because of Doppler effect
Consider a supersonic plane (mach 2) aproaching a stationary sound source (e.g a fog horn on a boat).
If I understand it correctly, the passengers in the plane can hear the sound twice. First at a 3 ...
2
votes
3answers
251 views
How many boats does it take to find an acoustic buoy by Doppler shift?
Inspired by this question on the Doppler shift, suppose there is buoy somewhere on the surface of the ocean emitting a pure frequency.
You get to place some boats wherever you want on the surface of ...
3
votes
5answers
628 views
Doppler effect of sound waves
I am looking for interesting ways to introduce the Doppler effect to students. I want some situations in nature or every day life, where a student is possibly surprised and may ask "how could it be"?
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