Part 1 Flashcards
Infrasound
<20 Hz
Audible Sound
20 - 20,000 Hz
Ultrasonic
> 20,000 to 20 Khz
Diagnostic ultrasound
2 to 15 Mhz
Time to complete one cycle
Unchanged by monographer
Sec/usec
Determined by : Source
Period
of cycles/ sec (affects ———-penetration & axial res)
Unchanged by monographer
Hertz
Determined by: source
Frequency
Rate work is performed
Unchanged by monographer
watts
Determined by Source
Power
Concentration of energy in a sound beam
Changed by sonographer
watts/cm^2
Determined by source
Intensity
Length/distance of single cycle
mm,cm
Changed by sonographer
Determined by source & Medium
wavelength
Rate sound travels in a medium
Unchanged by sonographer
m/sec
determined by : medium
prop speed
Amplitude , Power & Intensity are all related how ?
Direct
Period & Frequency are related how
Inverse
Power & area are related how
Inverse
Wavelength & frequency are related how
Inverse
Stiffness & Speed are related how
Direct
Speed & Density are related how
Inverse
Frequency , speed, intensity and power are related how
UNRELATED
3 bigness parameters changed by the output power
Amplitude
Power
Intensity
Intensity equation
Power/Area
Wavelength equation
Propagation Speed/Frequency
Soft tissue / wavelength equation
1.54 mm / Frequency
Speed equation
Frequency x wavelength
The speed in Air is
330 m/s
The speed in lung is
500 m/s
The speed in fat is
1450 m/s
The speed in Soft tissue/ Blood is
1540 m/s
The speed in tendon is …
1850 m/s
The speed of bone is
3500 m/s
Start of a pulse to the end of that pulse
Not changed by soon
Usec
Determined by - source
Pulse duration
Start of pulse to start of next pulse (on & off time)
Changed by sono
M/sec
Determined by source
PRP
of cycles per second
Changed by sono
1/sec Hz
Determined by source
PRF
% or fraction of time system transmits
Changed by sono
No units
Determined by source
Duty Factor