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

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SUMMARY

The discussion focuses on calculating the speed of an approaching vehicle using the Doppler Effect. A student in a parked car honks a horn at a frequency of 310.00 Hz, while an observer in an approaching vehicle measures the frequency at 342 Hz. The speed of sound in air is given as 340 m/s. The formula to calculate the speed of the approaching vehicle is derived from the Doppler Effect equation, specifically Vs = (Fo - Fs) / (Fo + Fs) * V, where Vs represents the speed of the source.

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  • Basic algebra for solving equations
  • Knowledge of physics concepts related to wave behavior
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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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