Question

"An ambulance is traveling north at 45.3 m/s, approaching a car that is also traveling north at 33.9 m/s. The ambulance driver hears his siren at a frequency of 656 Hz. Ambulance 45.3 m/s 33.9 m/s Car At what frequency does the driver of the car hear the ambulance’s siren? The velocity of sound in air is 343 m/s. Answer in units of Hz."

Answer 1

f = 681Hz

Step-by-step explanation:

Please see attachment below.

When the sound source is moving away from the listener the velocity of the sound source is positive and negative when moving towards the listener.

When listener is moving towards source the velocity of listener is taken as positive but negative otherwise

Answer 2

The driver hears it at 681.12Hz

Step-by-step explanation:

The equation for determining frequency of sound is given by:

F d= f (V + Vr)/(V - Vs)

Given :

f = 656Hz

V =343m/s

Vr = 33.9m/s

Vs = 45.3m/s

fd = 656 (343 - 33.9)/(343 - 45.3)

fd ,= 656 (309.1)/(297.7)

fd = 202,769.6/297.7

fd = 68.12Hz