Speed of Sound Wave: Car Moving 50m/s

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When a car moves towards a person at 50m/s and toots its horn, the speed of sound remains 340m/s relative to the air. However, the frequency of the sound will be perceived as higher due to the Doppler effect. The person does not measure the sound speed as 390m/s; it is consistently 340m/s. The Doppler shift affects the frequency, not the speed of sound itself. Thus, the key takeaway is that while the speed of sound is constant, its frequency changes based on the motion of the source.
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For a sound wave: A car is moving towards a person at 50m/s and toots its horn. Let's say the speed of sound relative to the air is 340m/s. Does the person measure the speed of the sound to be 390m/s or does it remain at 340m/s?
 
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Stilll 340 m/s, but the frequency of the horn will be Doppler shifted up.
 
olivermsun said:
Stilll 340 m/s, but the frequency of the horn will be Doppler shifted up.

Excellent, thanks for the help.
 

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