Final answer:
This question is about using the Doppler Effect to calculate the speed of an ambulance based on the frequencies of the siren as observed when the vehicle is approaching a stationary observer.
Step-by-step explanation:
The question involves the calculation of the speed of an ambulance using the Doppler Effect, which describes the change in frequency of a wave in relation to an observer moving relative to the source of the wave. The frequency of the ambulance siren is given (f), along with the frequency observed (fo) when the ambulance is approaching. Using the Doppler Effect formula for a source moving towards a stationary observer: fo = f * (v + vo) / v, where fo is the observed frequency, f is the emitted frequency, v is the speed of sound in the medium, and vo is the speed of the source (ambulance). One can solve for vo using the measured values and the speed of sound, typically converting to a common unit like kilometers per hour (km/h) or miles per hour (mph) for convenience.