EQUATIONS Phys & Instrumentation

power

amp²

frequency and period

f x p =1

wavelength

prop. speed / frequency

intensity

power / area

pulse duration (2)

cycles x period, cycles / frequency

PRP and PRF

PRP x PRF = 1

components of PRP

on and off time

spatial pulse length

cycles x wavelength

duty factor

pulse duration / prp

PREFIXES: billion, million, thousand, hundred, ten, tenth, hundredth, thousandth, millionth, billionth

giga, mega, kilo, hecto, deca, deci, centi, milli, micro, nano

INTENSITY ORDER: lowest to highest SPTA SPTP STPA SAPA SATA SATP

SPTP, SATP, SPPA, SAPA, SPTA, SATA

DECIBELS: 2x change, 10x change, 100x change, 1/4x change (+ or -)

+3, +10, +20, -6

total attenuation equation

(frequency / 2) x path length

attenuation coefficient equation

frequency / 2

half value layer thickness (cm) formula (2)

3/attenuation coefficient, 6/frequency

impedance equation

density x speed

incident intensity equation

reflected + transmitted intensity

Intensity reflection coefficient (IRC) and intensity transmission coefficient (ITC) equation

irc + itc = 1

IRC equation

[(impedance 2 - impedance 1)/(impedance 2 + impedance 1)]² x 100

ITC equation

transmitted / incident intensity x 100

time of flight equation

depth = 1.54 x go-return time /2

PRP equation using time of flight

depth x 13

PRF equation using depth

77000 cm/s / depth

quality factor equation

main frequency / bandwidth

frequency of transducer equation

sound speed in PZT / 2 x PZT width

fixed focal depth using wavelength

transducer diameter² / 4 x wavelength

fixed focal depth using frequency

transducer diameter² x frequency / 6

beam divergence angle equation

1.85 / transducer diameter x frequency

axial resolution 3 equations; equation for soft tissue

spl / 2, cycles x wavelength / 2, cycles x speed / s x frequency; 0.77 x cycles / frequency

lateral resolution equal to the…

beam diameter

axial resolution mnemonic and meaning

larrd, longitudinal, axial, radial, range, depth

lateral resolution mnemonic and meaning

lata, lateral, azimuthal, transverse, angular