I have been trying this problem for a couple of days:(adsbygoogle = window.adsbygoogle || []).push({});

Ultrasound reflected from an oncoming bloodstream that is moving at 30 cm/s is mixed with the original frequency of 2.5 MHz to produce beats. What is the beat frequency? (Velocity of sound in blood = 1540 m/s.)

I tried this as a doppler effect problem where the frequency is

(original frequency)*{v/(v-velocity of source)}. I then subtracted that from the original frequency to find the beat frequency, and came up with 487.1 Hz, but that was not the right answer. For v, I used 1540 m/s, and velocity of source was 0.3 m/s. Is there something I am missing in my approach to the problem?

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# Homework Help: Sound problem: Beat frequency

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