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

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The speed of sound in air is consistently 340 m/s, regardless of the speed of a jet moving at 100 m/s through the air. This is because the speed of sound is determined by the properties of the medium (air), not the speed of the sound source. The exercise highlights that the velocity of the source does not affect the wave velocity in the medium. There is a discussion about the confusion surrounding the independence of wave velocity from the medium, emphasizing that sound speed is indeed medium-dependent. The conversation also questions the source of the conflicting information regarding wave velocity.
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).
 
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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?
 

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
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