Answer :
Answer:
[tex]\Delta f=17959.2\ Hz[/tex]
Explanation:
Given:
- original frequency of the wave, [tex]f=4.4\times 10^6\ Hz[/tex]
- velocity of the blood stream moving away, [tex]v=1.4\ m.s^{-1}[/tex]
Doppler shift is given as:
[tex]\frac{f}{f_o} =\frac{s+v_s}{s-v_o}[/tex]
where:
s = velocity of ultrasound in blood = [tex]1570\ m.s^{-1}[/tex]
[tex]v_s=[/tex] velocity of sound source towards the observer
[tex]v_o=[/tex] velocity of the observer away from the source
[tex]\frac{4.4\times 10^6}{f_o} =\frac{1570+0}{1570-1.4}[/tex]
[tex]f_o=4396076.43\ Hz[/tex]
Therefore the shift in frequency:
[tex]\Delta f=f-f_o[/tex]
[tex]\Delta f=3923.56\ Hz[/tex]