The siren of an ambulance wails at 1395 Hz when the ambulance is stationary. What frequency will you hear after this ambulance passes you while traveling at 33.60 m/s? The speed of sound under the prevailing conditions is 343 m/s.

Answer: the frequency observed will be 1269.45hz

Explanation: according to the doppler effect,

Apparent frequency f' = (c / (c+u)) * f

f = real freq of sound of moving sound source

c = speed of sound in air

u = speed of moving sound source

f' = (343 / (343+33.6)) * 1395

f' = 1269.45hz