Una ambulancia se desplaza hacia el norte a 23,5 m/s. su sirena emite un sonido de 500hz de frecuencia. calcular la frecuencia aparente que percibe un observador que viaja en su auto, también hacia el norte , a 28,6, cuando:

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The apparent frequency would be  

f' = 493.26 Hz

Step-by-step explanation:

This a Doppler's effect problem. This effects produces a slight change in the frequency of a traveling wave, due to the effect of the velocity of the receiver (observer).

The formula used to describe the change, as both vehicles are moving away of each other:

f' = [ (Vwave + Vobserver) / (Vwave + Vsource ) ]*f

Where  

Vwave = 340 m/s ( speed of sound)

Vobserver = 18.6 m/s (observer = car)

Vsource = 23.5 m/s (speed of the ambulance = source)

f = 500 Hz (frequency of the sound)

We just need to substitute in the equation

f' = [(340+ 18.6) / (340+ 23.5)] * 500 Hz

f' = [0.9865] * 500 Hz = 493.26 Hz

f' = 493.26 Hz

this story was prepared by jim

mccullaugh in los angeles and

al stewart in new york.

new york the colossal success of "top gun" appears to have dramatically altered madison avenue's

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cd sales totaled 10.7 million units

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step-by-step explanation:

$9.41

step-by-step explanation: