Why is the speed of sound from a jet moving at 100m/s through air still 340m/s?

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SUMMARY

The speed of sound in air is consistently 340 m/s, regardless of the speed of the source, such as a jet moving at 100 m/s. This phenomenon is explained by the principle that wave velocity is independent of the source's motion relative to the medium. The discussion highlights a common misconception that wave velocity is dependent on the medium, clarifying that the speed of sound remains constant in a given medium, which in this case is air.

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Gear2d
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Homework Statement



Speed of sound in air is 340m/s. Sound from a jet, moving a 100m/s through the air, will have a speed of:

Homework Equations



Doppler effect, and v = Sqrt(bulk/density)

The Attempt at a Solution



The answer for this is 340m/s. I was wondering why. Because all the book states is that wave velocity is INDEPENDENT of medium (I thought velocity of a wave was medium dependent).
 
Last edited:
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Gear2d said:
The answer for this is 340m/s. I was wondering why.
The velocity of sound is 340 m/s with respect to the medium (air). The point of the exercise is that the speed of the source (the jet) is irrelevant.
Because all the book states is that wave velocity is INDEPENDENT of medium (I thought velocity of a wave was medium dependent).
That's a pretty wild statement. You're right, the speed of sound most definitely depends on the medium. (What book is that, by the way?) What was the context of that statement?
 

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