Question

Need some help please! TIA

pler blood flow unit emits ultrasound at 4.8 MHz What is the frequency shift of the ultrasound reflected from blood moving in an artery at a speed of 0.25 m/s? Express your answer with the appropriate units Af-Value Units

Answer 1

Part A : The frequency shift of ultrasound reflected from blood which will be given by -

$\Delta$f = 2 v f / c

where, c = speed of blood = 1540 m/s

v = speed of blood in an artery = 0.25 m/s

f = frequency emitted by blood flow = 4.8 x 10⁶ Hz

then, we get

$\Delta$f = [2 (0.25 m/s) (4.8 x 10⁶ Hz)] / (1540 m/s)

$\Delta$f = [(2.40 x 10⁶ m/s²) / (1540 m/s)]

$\Delta$f = 1558.4 Hz

converting Hz into kHz :

$\Delta$f $\approx$ 1.56 kHz