An ambulance is generating a siren sound at a frequency of $2,400 \mathrm{~Hz}$. The speed of sound is $345.0 \mathrm{~m} / \mathrm{s}$. If the ambulance is traveling at a velocity of $24.00 \mathrm{~m} / \mathrm{s}$ away from the stationary observer, then what is the frequency of the siren perceived by the observer?
A) $2,244 \mathrm{~Hz}$
B) $2,266 \mathrm{~Hz}$
C) $2,306 \mathrm{~Hz}$
D) $2,375 \mathrm{~Hz}$
E) $2,210 \mathrm{~Hz}$

Question

Quizplus · Accepted Answer

The frequency perceived by the observer can be calculated using the Doppler effect formula for a source moving away from the observer: $f' = f \frac{v}{v + v_s}$, where $f'$ is the perceived frequency, $f$ is the source frequency, $v$ is the speed of sound, and $v_s$ is the speed of the source. Plugging in the given values: $f' = 2400 \frac{345.0}{345.0 + 24.00} = 2244 \mathrm{~Hz}$.

An Ambulance Is Generating a Siren Sound at a Frequency 2,400 Hz2,400 \mathrm{~Hz}2,400 Hz

An Ambulance Is Generating a Siren Sound at a Frequency $2,400 \mathrm{~Hz}$