Hmmmm. I am uncertain of what your text has presented, so let me try this...
doppler=fo-f=2fo(v/vsound) for head on doppler, if one is observing at an angle, cosTheta should be a multiplier.
.1khz=2*3.5M*v/vs
now what is vs: near speed in water, 1496m/s . calculate v
I get v approximately equal to
.1k*1496/2*3.5M = 0.021m/s or about 2cm/s which is a reasonalble flow rate for blood.
A cardiologist uses an ultrasound scanner with an operating frequency of 3.5 MHz that can detect Doppler frequency shifts as small as 0.1 kHz. What is the smallest flow velocity detectable with this device?
Two frequencies are given so I know I have to convert the units but im thinking if I have to find the wavelength and then velocity. I'm looking at all the formulas and i'm just having trouble with this problem
I'm thinking about using this formula, and stating that vs = vair= 343 m/s
f^' = fo (1 + V/vs)
2 answers
yes that's right, thank you very much.
1 answer