The Doppler Effect

[Mariasde233]

The mean velocity of blood flow in the aorta during systole is 1.5 × 10–2 m / s. What is the frequency change in an instrument with a signal frequency of 105 Hz? (speed of sound in blood, 1570 m / s).

[bobbinwales]

did doppler at night school many moons ago

https://www.omnicalculator.com/physics/doppler-effect

[bobbinwales]

thats the one where the police siren frequency changes as it drives past

[JimF]

± 3%.

Will be slightly lower for diabetics.

[Karolina82]

Is this an ultrasound machine for imaging purposes?
The frequency is too low.
Should it be perhaps 105kHz?

[mibn2cweus]

1570m/s / 0.015m/s = 104667

105 / 104667 = 0.001hz

Some of the unit values as stated in the question are suspect.