How to Calculate the Speed of an Approaching Vehicle Using Doppler Effect?

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To calculate the speed of the approaching vehicle using the Doppler effect, the formula needs to be adjusted for an object moving towards the observer. The correct formula is Vs = (Fo - Fs) / (Fo + Fs) * V, where Fs is the source frequency (310 Hz), Fo is the observed frequency (342 Hz), and V is the speed of sound (340 m/s). By substituting the values into the formula, the speed of the approaching vehicle can be determined. The student is encouraged to refer to previously discussed threads for similar calculations. Understanding the Doppler effect's application is crucial for solving this problem effectively.
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Test tomorrow...please help!

Homework Statement


A student in a parked car honks the horn, which has a `proper' frequency of 310.00 Hz. An observer in an approaching vehicle measures the frequency of the sound to be 342 Hz. Calculate the speed of the approaching vehicle. Use 340 m/s as the speed of sound in air.


Homework Equations





The Attempt at a Solution


Fs = 310 Hz
Fo = 342 Hz
Vo = 0 m/s
V = 340 m/s
Vs = ?

I know
Vs = (Fs - Fo / Fs + Fo) * V
if the object is going away from the observer
but how I do calculate if the object is approaching the person?
 
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