COMPREHENSIVE QUESTIONS SOLUTIONS
GRADED A PLUS IMAGING PHYSICS PRACTICE
PACKAGE
◉ If the frequency of sound is above 20 kHz it is called
Answer: ultrasound
◉ If the frequency of sound is between 16 Hz and 20 kHz it is called
Answer: audible sound
◉ Which of the following is not among the spectrum of
electromagnetic waves?
A. X-RAYS
B. ULTRASOUND
C. ULTRAVIOLET
D. INFRARED
E. VISIBLE LIGHT
Answer: ultrasound
◉ The term Hertz denotes
,Answer: frequency, cycle per second
◉ An ultrasound transducer converts
Answer: electrical energy into mechanical energy and vice versa
◉ Name 4 examples of a transducer
Answer: battery, loudspeaker, light bulb, human being
◉ When electric voltage is applied on both faces of a piezoelectric
crystal, the crystal will
Answer: increase or decrease in size depending on the voltage
polarity
◉ The abbreviation 5 MHz denotes
Answer: five million cycles per second
◉ The function of the damping material in the transducer housing is
to
Answer: reduce pulse duration, improve axial resolution, reduce
spatial pulse length
◉ What is the velocity of ultrasound in human soft tissue at 37°C?
Answer: 1540 m/s
,◉ in physical science, the word period denotes
Answer: time to complete one cycle
◉ Longitudinal waves are characterized by
Answer: motion of particles parallel to the axis of wave propagation
◉ Transverse waves are characterized by
Answer: motion of particles perpendicular to the axis of wave
propagation
◉ Ultrasound wave propagation causes displacement of particles in
a medium. The regions of greatest particle concentration are
Answer: compressions
◉ Ultrasound wave propagation causes displacement of particles in
a medium. The regions of lowest particle concentration are called
Answer: rarefactions
◉ The prefix piezo- is derived from a Greek word that denotes
Answer: pressure
, ◉ Other than depth, longitudinal, and range/radial resolution, what
is another term for the ability to distinguish two objects parallel to
the ultrasound beam?
Answer: axial resolution
◉ electrical connector
Answer: #123
◉ backing material
Answer: #124
◉ damping material
Answer: #125
◉ tuning coil
Answer: #126
◉ housing
Answer: #127
◉ face material
Answer: #128