A factory siren emits a sound at 900hz.what frequency will be heard by the driver of a car traveling at 100km.h away from the factory?
2 answers
Help me please!
Vd=100,000m/1h * 100000m/3600s=27.8 m/s
= Velocity of driver.
Fd = ((Vs-Vd)/(Vs+Ve))*Fe
Fd = ((343-27.8)/(343+0))*900Hz
Fd = (315.2/343) * 900 = 827 Hz = Freq.
heard by driver.
Vs = Velocity of sound in air.
Ve = Velocity of the sound emitter
(siren).
Fe = Freq. emitted.
= Velocity of driver.
Fd = ((Vs-Vd)/(Vs+Ve))*Fe
Fd = ((343-27.8)/(343+0))*900Hz
Fd = (315.2/343) * 900 = 827 Hz = Freq.
heard by driver.
Vs = Velocity of sound in air.
Ve = Velocity of the sound emitter
(siren).
Fe = Freq. emitted.
2 answers