WorksheetsUltrasound Physics Chapters 4 and 5, Pulsed US & Intensities
Total questions: 34
Worksheet time: 17mins
Which of the following is NOT one of the seven parameters of sound waves?
Frequency
Temperature
Amplitude
Wavelength
Ultrasound uses which of the following types of waves?
Only CW
Only PW
Both CW and PW
Neither CW nor PW
Based on the diagrams, how do pulsed waves differ from continuous waves in the context of image creation?
Pulsed waves alternate between transmitting and receiving, while continuous waves only transmit
Pulsed waves are always on, while continuous waves are always off
Continuous waves alternate between transmitting and receiving, while pulsed waves only transmit
Both types of waves alternate between transmitting and receiving
What is the difference in the two types of waveforms represented in this image?
The amplitude of two different waves
The frequency of two different waves
A single cycle versus multiple cycles in a pulse
The speed of sound in different media
How does pulsed wave ultrasound differ from continuous wave ultrasound?
They have an on and an off time
They are always continuous
They never repeat
They have no pattern
Which of the following best describes the difference between a continuous wave and a pulse?
A continuous wave has no breaks, while a pulse has groups of cycles with clear breaks
A pulse is always louder than a continuous wave
A continuous wave is random, while a pulse is regular
A pulse has no cycles, while a continuous wave does
What is the typical number of cycles per pulse emitted by clinical ultrasound to create a grayscale (b-mode) image?
2-4 cycles
5-7 cycles
8-10 cycles
10-12 cycles
Which of the following parameters is affected by a decrease in the imaging depth? (more than one may be correct)
Increased PRF
Decreased PRF
Increased PRP
Decreased PRP
Imaging depth does not affect any of the listed parameters
Which of the following is a correct unit for measuring pulse duration?
Hertz (Hz)
Meters (m)
Microseconds (μs)
Volts (V)
Pulse duration is determined by which of the following?
The operator
The machine
The patient
The environment
How does pulse duration change when the period time is short?
Pulse duration is long.
Pulse duration is short.
Pulse duration is unaffected.
Pulse duration becomes infinite.
Pulse duration is inversely related to which of the following?
Number of cycles
Period time
Frequency
Amplitude
Based on the diagrams, what can be inferred about the relationship between the number of cycles and pulse duration?
Fewer cycles result in a longer pulse duration.
More cycles result in a shorter pulse duration.
More cycles result in a longer pulse duration.
The number of cycles does not affect pulse duration.
Which unit is commonly used to measure pulse repetition frequency (PRF)?
kHz or derivative of Hz
Meters per second
Joules
Watts
Which formula correctly represents the relationship between PRP and PRF?
PRP x PRF = 1
PRP + PRF = 1
PRP / PRF = 1
PRP - PRF = 1
Based on the diagram, what does the number of wave groups passing a point in one second represent?
Pulse Repetition Frequency (PRF)
Wavelength
Amplitude
Speed of sound
What is the relationship between PRP and PRF?
PRP is a reciprocal of PRF
PRP is equal to PRF
PRP is double PRF
PRP is unrelated to PRF
A sonographer wants to increase the PRF. What should they do to the imaging depth?
Decrease the imaging depth
Increase the imaging depth
Keep the imaging depth the same
PRF does not depend on imaging depth
Given the reciprocal relationship between PRP and PRF, what would be the effect on PRF if PRP is halved?
PRF is halved
PRF is doubled
PRF remains unchanged
PRF becomes zero
Duty factor (DF) is inversely related to which of the following?
Pulse duration (PD)
Frequency
Pulse repetition period (PRP)
Amplitude
What is the formula for wavelength (λ) in terms of propagation speed (c) and frequency (f)?
λ = c/f
λ = f/c
λ = c × f
λ = 1/c
Which of the following best describes the Duty Factor in ultrasound physics?
Duty Factor = (Pulse Duration / PRP) × 100
Duty Factor = (PRP / Pulse Duration) × 100
Duty Factor = (PRF / Pulse Duration) × 100
Duty Factor = (Pulse Duration × PRP) × 100
How can the sonographer change the PRP, PRF, and DF?
Change transducers
Roll the patient
Imaging depth
Cannot be changed
What happens when you change the imaging depth in ultrasound?
It changes the listening time for the soundwave to return to the transducer.
It changes the color of the image.
It increases the frequency of the soundwave.
It decreases the size of the transducer.
How does the process of sending and waiting for pulses contribute to image formation in medical imaging?
Each pulse creates a scan line, and multiple scan lines form the complete image
Each pulse creates a full image instantly
Each pulse erases the previous image
Each pulse only measures temperature
How does a shorter Spatial Pulse Length (SPL) affect axial resolution and image detail?
It improves axial resolution and provides better detail.
It decreases axial resolution and reduces detail.
It has no effect on axial resolution.
It only affects lateral resolution, not axial resolution.
What parameter is demonstrated in this graphic, the area between the purple bars? (pay attention to the description)
Pulse repetition frequency
Pulse repetition period
Pulse duration
Spatial Pulse Length
If the imaging depth is shallow, what can be said about PRF?
PRF is low
PRF is high
PRF is zero
PRF is unchanged
What does a duty factor of 0% indicate about the machine status?
continuous wave ultrasound
the machine is off
a decrease in depth
pulsed wave ultrasound
Which term is used to describe the maximum value of intensity in pulsed waves?
Average
Pulsed
Peak
Temporal
Which of the following best describes "intensity" in the context of pulsed waves?
The maximum value
Beams power divided by its area
Refers only to the transmit time
Relating to time, all time transmit and receive
When the ultrasound machine is imaging in grayscale, what is the usual Duty Factor (DF)?
100%
1-10%
Less than 1%
50%
If the duty factor increases, what happens to the temporal average (TA) intensity in an ultrasound system?
The TA intensity increases
The TA intensity decreases
The TA intensity remains the same
The TA intensity becomes zero
What does the beam uniformity ratio (BUR) compare?
