a A sound source producing 416kHz waves moves toward a stati

(a) A sound source producing 4.16-kHz waves moves toward a stationary listener at one-half the speed of sound. What frequency will the listener hear? (The speed of sound is 344 m/s.)
Hz

(b) Suppose instead that the source is stationary and the listener moves toward the source at one-half the speed of sound. What frequency does the listener hear?
Hz

Solution

a) fspeed of person, v = vs/2

v = 0.5 * vs

frequency heard = fo*(Vs)/(vs- v)

frequency heard = 4.16 * Vs/(Vs-0.5Vs)=8.32kHz

frequency heard by the observer =8320Hz

b)for speed of source, v = vs/2

v = 0.5 * vs

frequency heard = fo*(Vs + v)/vs

frequency heard = 4.16 * (0.5 vs + vs)/vs

frequency heard = 6.24 kHz

frequency heard by the observer =6240 Hz