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lzh
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Assume: Take the speed of sound in air to be 343 m/s.
A bat, moving at 5.9 m/s, is chasing a flying insect.
The bat emits a 46 kHz chirp and receives back an echo at 46.26 kHz.
At what speed is the bat gaining on its prey? Answer in units of m/s.
I tried this:
f=initial frequency
fo=observed frequency
x= velocity of insect
fo/f=(343+Vbat)/(343+x)
but it doesn't seem to work:
46260/46000=(343+5.9)/(343+x)
1.0056=348.9/(343+x)
343+x=346.94
x=3.939
then i take the velocity of the bat:
5.9-3.939=1.96
this answer isn't right though, but I don't see why.
A bat, moving at 5.9 m/s, is chasing a flying insect.
The bat emits a 46 kHz chirp and receives back an echo at 46.26 kHz.
At what speed is the bat gaining on its prey? Answer in units of m/s.
I tried this:
f=initial frequency
fo=observed frequency
x= velocity of insect
fo/f=(343+Vbat)/(343+x)
but it doesn't seem to work:
46260/46000=(343+5.9)/(343+x)
1.0056=348.9/(343+x)
343+x=346.94
x=3.939
then i take the velocity of the bat:
5.9-3.939=1.96
this answer isn't right though, but I don't see why.
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