Font size
WorksheetsUltrasound physics
Total questions: 32
Worksheet time: 16mins
Which of these factors has greatest influence on pulse repitition period
Crystal thickness
Display depth
Impedance of medium
Attenuation of sound beam
The time frame from the beginning of a pulse to its end is
Period
Pulse duration
Pulse length
PRF
Speed of ultrasound in soft tissue is closest to:
1,540 km/sec
1.54 cm
1,500 m/s
1,540 mm/sec
The duty factor for continuous wave ultrasound is
1%
10.0
1.0
0.0
What is the fraction of time that sound is transmitting
Pulse duration
Duty factor
Period
PRF spatial duration
Propagation speed is determine by the medium. Which of the following is correct?
Density increases,speed increases,stiffness Increases,speed increases
Density increases,speed decreases,stiffness increases,speed increases
Density decreases,speed decreases, stiffness increases,speed increases
Density increases,speed decreases,stiffness increases,speed decreases.
The pulse repitition frequency is the number of pulses occurring per
Wave
Echo
Reflection
Second
Temporal refers to
Space
Peak
Time
Average
Which of the following has the lowest intensity?
SPTP
SATP
SPTA
SATA
Highest intensity?
SATA
SATP
SPTP
SPTA
SPPA stands for
(a)
Unit of measurement of spta
Hz
Watts
Db
W/cm²
Which would decrease beam intensity?
Decreasing receiver gain
Increasing focus
Increasing output
Increasing beam area
If you adjust the acoustic power by -3db which describes this adjustment
Intensity has been halved
Intensity has been quartered
Intensity has been doubled
Intensity decreased by 3
Ultrasonic energy diverted in a omni direction is referred to as
Reflection
Diffusion
Rayleigh scattering
Scattering
Attenuation coefficient in soft tissue
5 db/ cm
.5 db/ cm
3 db /cm
1 db
In soft tissue the attenuation coefficient in db/cm is equal to one half
Frequency/Hz
Frequency/MHz
Frequency/wavelength
Impedance/rayls
Which tissue has the least attenuation
Air
Blood
Water
Bone
What is the use of gel on a patient's skin?
Reduce friction
Remove air
Improve reflections
Soften skin
Attenuation includes all of the following except
Enhancement
Scattering
Reflection
Absorption
Specular reflection occurs only
At high frequency
At smooth surface
With real time ultrasound
With focused beam
The imaging depth (a) as frequency increases
Attenuation consists of (pick3)
Absorption
Refraction
Scattering
Reflection
Enhancement
There is approximately _____ db of attenuation per cm for each MHz of frequency.
0.1
1.0
0.5
5
Start of a pulse to the start of a next pulse including listening time
Pulse repetition frequency
Pulse repetition period
Pulse duration
Duty factor
Fraction of time sound is transmitting
Decibels
Duty factor
Attenuation
Impedance
Number of pulses occurring per second
Pulse rep period
Pulse rep frequency
Pulse duration
Start of a pulse to the end of that pulse
(a)
What determines impedance ? (Pick 2)
Sound source
Density
Medium
Stiffness
What determines rarefraction (pick2)
Medium
Sound source
Oblique incidence
Intensity
Attenuation means to
(a)
Pulse repetition freq. Is adjustable by sonographer
True
False
