Doppler Shift Equation: How to Calculate Frequency of a Stationary Train

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SUMMARY

The discussion centers on calculating the frequency detected by a stationary train when a moving train blows a horn at 305 Hz while traveling at 31 m/s. The correct formula to use is f' = f(V + Vd / V - Vs), where V is the speed of sound in air, and Vs is the speed of the source. The expected detected frequency is 340 Hz, which can be derived by substituting the appropriate values into the formula.

PREREQUISITES
  • Understanding of the Doppler Effect
  • Familiarity with the speed of sound in air (approximately 340 m/s)
  • Knowledge of basic algebra for manipulating equations
  • Experience with frequency calculations in physics
NEXT STEPS
  • Study the Doppler Shift Equation in detail
  • Learn how to calculate frequency changes for moving sources and observers
  • Explore the effects of different speeds on sound frequency detection
  • Investigate applications of the Doppler Effect in real-world scenarios
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Physics students, educators, and anyone interested in understanding sound wave behavior and frequency calculations in motion scenarios.

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A train moving toward a detector at 31m/s blows a 305-Hz horn. What frequency is detected by a statiory train?

Using the equation f´= f(V + Vd/ V - Vs)

The answer is supposed to be 340-Hz but I don't understand how to get it. Mind helping me out?
 
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anyone know?
 
I do not recognize the formula. My scientific encyclopedia gives this for the source approaching the detector:

[tex]f' = f(\frac{1}{1-\frac{v}{v_s}})[/tex]

where v_s is the speed of sound in air.
 

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