(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

You're flying in an aircraft at 46 m/s. An eagle flies directly towards you at 11 m/s. Speeds are relative to ground.

The eagle emits a cry at 3400 Hz, and the speed of sound is 330 m/s. What frequency do you hear?

2. Relevant equations

[tex]f_o = f_s\left( \frac{1\pm\frac{v_o}{v}}{1\mp\frac{v_s}{v}} \right)[/tex]

Because the observer and source are both moving towards each other (presumably?),

[tex]f_o = f_s\left( \frac{1+\frac{v_o}{v}}{1-\frac{v_s}{v}} \right)[/tex]

3. The attempt at a solution

Seems simple enough, but

[tex]f_o = 3400\left( \frac{1+\frac{46}{330}}{1-\frac{11}{330}} \right)[/tex]

Works out to 4902.8213 Hz, a wrong answer. This problem seemed straightforward, but I'm not sure what I'm missing.

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# Homework Help: Doppler Effect II (Both observer and source in motion)

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