Question number 4 on the ultrasound homework asks for the approximate acoustical impedance Z of the matching layer in a single-layer system. The formula for this is Z = SQRT( Z1 * Z2 ) where Z1 is the acoustic impedance of PZT (30 * 10^6 kg/s*m^2) and Z2 is the acoustic impedance of the tissue. Are we to assume the tissue is adipose tissue with an acoustic impedance of 1.42 * 10^6 kg/s*m^2?

Question number 4 on the ultrasound homework asks for the approximate acoustical impedance Z of the matching layer in a single-layer system. The formula for this is Z = SQRT( Z1 * Z2 ) where Z1 is the acoustic impedance of PZT (30 * 10^6 kg/s*m^2) and Z2 is the acoustic impedance of the tissue. Are we to assume the tissue is adipose tissue with an acoustic impedance of 1.42 * 10^6 kg/s*m^2?

Strictly, it would be skin, but it really does not make much difference. Choose adipose or muscle, if you wish.

For question 7, what c are we suppose to use for the maximum flow velocity equation?

Is it safe to assume c = 1540 m/s in this case?