Apparent frequncy of sound heard?

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SUMMARY

The discussion centers on the Doppler effect as it applies to sound frequency changes due to relative motion. A car traveling at 30 m/s approaches a stationary sound source emitting a frequency of 5000 Hz, resulting in an apparent frequency of 5455 Hz as calculated using the formula ((330+30)/330) x 5000. However, when considering the reflection of sound from the car, the frequency perceived by the car is not the same as the frequency it reflects, leading to a frequency of 6001 Hz being noted as the apparent frequency reflected from the car.

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Homework Statement



A car is moving in a straight line at 30m/s approaches a stationary source which emits sound of frequency 5000hz. If the speed of sound is 330m/s . The apparent frequncy received by car is ((330+30)/ 330) x 5000= 5455hz.
What 's the frequency reflected form the car? the ans given is 6001hz.

why not the frequency received by the car = frequency of sound reflected by the car? which means the apparent frequency reflected form the car is also = 5455hz?

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The Attempt at a Solution

 
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The reflected sound is at the frequency you say, but only when "heard" from the car. The car itself is a source moving with respect to the medium, in the direction of the emitted (reflected) sound.
 

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