Shock Wave Front: How Does Source Movement Create Waves?

AI Thread Summary
When a source is not vibrating, it does not generate waves through vibration, but its movement can still disturb the medium. If the source moves faster than the speed of sound, it creates a shock wave due to the source being ahead of the sound waves it generates. This phenomenon is related to the Doppler effect, where waves superimpose behind the moving source. Visualizing the moving source and wave fronts helps clarify how these waves combine. Understanding these concepts leads to a clearer grasp of shock wave formation.
tina21
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Homework Statement
When a vibrating source moves through a medium with speed V, speed of propagation of wave is v. A conical wavefront is set up independent of time. What happens when the source is not vibrating?
Relevant Equations
Sin(theta) = v/V
So when the source is not vibrating, it is not setting waves due to vibration? But it is moving so it is still causing disturbance in the medium ... And I happened to read that if the source is moving faster than the speed of sound, a shock wave is set up. How ?
 
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Read about Doppler's effect; the shock wave is there because the source is always ahead of the sound wave it creates; behind the source, there will be a region where waves superimpose; sketch the moving plane, sketch few wave fronts and you will see how they combine. Look up Sonic Bum.
 
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I understand now. Thank you so much :smile:
 
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