An airplane traveling at half the speed of sound emits a sound of frequency 5.84 kHz. (a) At what frequency does a stationary listener hear the sound as the plane approaches?

Stationary listener frequency = 77.68 kHz

Explanation:

Given:

Speed of airplane = 344/2 = 172 m/s

Sound of frequency = 5.84 kHz

Computation:

f0 = fs[(v+v0)/(v-vs)]

f0 = 5.84[(344+0)/(344-172)]

f0 = 5.84[(344)/172]

Stationary listener frequency = 77.68 kHz

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