'An ambulance with a siren emitting a whine at 1200 Hz is catching up to a cyclist pedalling a bike in the same direction at 2.80 m/s. Before being passed, the cyclist hears a freqency of 1261 Hz. There is a wind of 10.0 m/s helping the cyclist along. The speed of sound in air is 343 m/s. Calculate the speed of the anbulance.'(adsbygoogle = window.adsbygoogle || []).push({});

Now i know the ambulance is the source and the cyclist is the listener. So i use the equation:

FL = FS (v-vL/v-vS)

FL = 1261 Hz

Fs = 1200 Hz

v = 343 + 10

vL = vs-2.8

and solve for vS, but i cannot get the right answer. My answer is always turning out to be 297 m/s which is definitly wrong. Can someone tell me where I'm going wrong? any help would be appriciated. Thanks

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# Homework Help: Sound In Air Problem

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