"Doppler Effect: Applying a 35 m/s Car

AI Thread Summary
The discussion centers on a physics problem involving the Doppler Effect, where a car traveling at 35 m/s approaches a stationary whistle emitting a 220 Hz sound. The speed of sound is given as 343 m/s, and the main question is about determining the speed of sound relative to the driver of the car. One participant calculated the frequency perceived by the driver as 242 Hz but expressed confusion about the question's intent. Clarification suggests that to find the relative speed, one should consider the velocities of both the car and the sound, indicating a need to add them due to their collision course. The conversation highlights the complexities of interpreting the problem correctly.
dietcokegal
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Homework Statement



A car moving at 35 m/s approaches a stationary whistle that emits a 220 Hz sound. The speed of sound is 343 m/s. What is the speed of sound relative to the driver of the car?

Homework Equations



fo = fs [1 +/- vo/v] / [1 +/- vs/v]

The Attempt at a Solution



Dont know how to do this problem at all. I am not understanding what the question is even asking for. I solved for the frequency that the observer in the car is hearing -- 242 Hz. Not sure how to figure out the question being asked.
 
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Well, the speed of something relative to something else would be that something minus the value of the something else.

So it looks like all you need to do is subtract the speed of sound from the speed of the car (but remember that they are on a collision course, so you would really by adding the two velocities).

Eh, that's an oddly phrased question.
 

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