To solve this problem we will apply the concepts related to the Doppler effect. The Doppler effect is the change in the perceived frequency of any wave movement when the emitter, or focus of waves, and the receiver, or observer, move relative to each other. The image ambulance moves from left to right.
[tex]v_S = \frac{f_+-f_-}{f_-+f_+}*v[/tex]
Here,
v = Velocity of sound
[tex]f_+[/tex] = Frequency of approaching sound waves
[tex]f_-[/tex] = Frequency of falling sound wave
Replacing with our values we have,
[tex]v_s = \frac{550-450}{450+550} (343)[/tex]
[tex]v_s = \frac{10}{1000}(343)[/tex]
[tex]v_s = 34.3m/s[/tex]
Therefore the velocity is 34.3m/s
