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Friday, October 29, 2010
Ch10 2 #2
This uses the Doppler Effect to shift the frequency
3 comments:
Anonymous
said...
How do we go about doing this problem using the Doppler effect? f'=v/(v-v) *f and we plug in what exactly?
3 comments:
How do we go about doing this problem using the Doppler effect?
f'=v/(v-v) *f and we plug in what exactly?
how are you supposed to figure this out?? somebody help!!!
f = f0 ((v- v0)/v ) and since v= speed of sound 340m/s so we can rewrite as (1 - v0/v)
what to reduce the freq from the whistle for you to hear. SO if whistle is at 21Hz and you hear 20hz, you need a freq of 20/21 = 1 - v0/v
So its about 1/21 of the speed of sound.
340m/s / 21 = about 16m/s
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