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Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
What is the vertical axis of a graph called? a. z-axis b. x-axis c. y-axis d. time-axis - ansc. y-axis What is the name of the horizontal axis of a graph? a. z-axis b. x-axis c. y-axis d. red axis - ansb. x-axis How are scores on the ultrasound board exams related to study time? a. inversely b. conversely c. directly d. unrelated - ansc. directly How are caloric intake and weight related? A. inversely B. partially C. reciprocally D. directly - ansd. directly How is weight related to a sonographer's time spent exercising? a. inversely b. conversely c. directly d. unrelated - ansA. inversely What is the reciprocal of 1,000? a. one-hundreth b. 1, c. 0. d. one-millionth - ansc. 0. What is the reciprocal of 5? a. one-hundredth b. 5 c. 1/ d. one-millionth - ansc. 1/ What is the reciprocal of 1/10? a. one-hundredth b. 10 c. 1/ d. one-millionth - ansb. 10
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
A sack contains 6 pounds of flour. The contents of the bag are increased by a factor of 5. How much flour is in the bag? a. 6 pounds b. 11 pounds c. 60 pounds d. 30 pounds - ansd. 30 pounds A bouquet has 30 flowers. The size of the bouquet is decreased by a factor of 3. How many flowers remain? a. 27 b. 0 c. 10 d. 15 - ansc. 10 Which of the following is not a measurement of area? a. square cm b. meters squared c. cubic meters d. feet x feet - ansc. cubic meters A sonographer measures the perimeter of an anatomical structure. Which of the following choices is a reasonable value for the measurement? A. 6 cm B. 5 cc C. 15 mm D. 18 dB - ansc. 15mm What are the units associated with the circumference of a circle? a. mm b. mm c. cm d. m4 - ansa. mm The volume of a cystic structure is estimated from sonographic data. Which of the following is an acceptable measurement of this volume? a. 6 b. 6cm c. 6cm d. 6cm3 - ansd. 6cm The speed of red blood cells traveling through a blood vessel is 750 cm/sec. You are asked to measure this speed in miles per hour. What information would be sufficient for you to complete your task? A. how many seconds in a minute and how many blood cells in the vessel B. the number of miles in a meter C. how many seconds per hour and the number of miles in a centimeter
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
f. giga 5. billions Which term is the reciprocal of mega? A. nano B. kilo C. macro D. micro - ansd. micro How can the volume of an irregularly shaped object be measured most accurately? a. by visual inspection b. by its weight c. by immersing it in water d. by ultrasound scanning it - ansc. by immersing it in water What term is used to describe the effects of an ultrasound wave on living tissues? a. toxic effects b. acoustic propagation properties c. biological effects d. transmission properties - ansc. biological effects As sound travels through a medium, what term describes the effects of the medium on the sound wave? a. toxic effects b. acoustic propagation properties c. bioeffects d. transmission properties - ansb. acoustic propagation properties Which of the following is true of all waves? a. they travel through a medium b. all carry energy from one site to another c. their amplitudes do not change d. they travel in a straight line - ansb. they all carry energy from one site to another Which of the following types of waves do not require a medium in order to propagate? (More than one answer may be correct). a. light b. heat c. sound d. television - ansA. light B. heat D. television Which of the following describes the characteristics of a sound wave? a. longitudinal, non-mechanical b. mechanical, transverse c. transverse, acoustic d. mechanical, longitudinal - ansd. mechanical, longitudinal Sound is best described as _____.
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
A. a series of compressions and rarefactions B. a transverse wave C. a wave humans can hear D. an oblique displacement of acoustic energy - ansa. a series of compressions and rarefactions All of the following are true about sounds waves except: a. they are mechanical b. they are transverse c. they carry energy from place to place d. they generally travel in a straight line - ansb. they are transverse Which of the following 8 selections are acoustic variables?
- frequency
- pressure
- propagation speed
- wavelength
- voltage
- intensity
- motion of particles in the wave
- density - ans2. pressure
- motion of particles in the wave
- density What are the units of a pressure measurement of an acoustic wave? (More than one answer may be correct). a. atmospheres (atm) b. pascals (Pa) c. millimeters of mercury (mm Hg) d. pounds/sq. inch (lb/in^2) - ansa. atmospheres (atm) b. pascals (Pa) c. millimeters of mercury (mm Hg) d. pounds/sq. inch (lb/in^2) Sound can be characterizes as: a. energy flowing through a vacuum b. a variable c. cyclical oscillations in certain variables d. a principle of acoustics - ansc. cyclical oscillations in certain variables Which units are appropriate for pressure: a. lb/in^ b. fahrenheit degrees c. miles d. Pa e. cm
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
c. mechanical d. transverse - ansd. transverse A particle within a transverse wave is traveling vertically. What is the direction of the wave's propagation? a. horizontal b. vertical c. diagonal; both horizontal and vertical d. cannot be determined - ansa. horizontal Waves that exist at the same location and time will combine. What is this called? a. inference b. rarefaction c. interference d. longitudinal interaction - ansc. interference Two waves arrive at the same location and interfere. The resultant sound wave is smaller than either of the two original waves. What is this called? a. constructive interference b. angular interaction c. destructive interference d. in-phase waves - ansc. destructive interference A pair of waves are in phase. What occurs when these waves interfere? a. reflection b. constructive interference c. refraction d. destructive interference - ansb. constructive interference What is the range of periods commonly found in waves produced by ultrasound systems? a. 0.001 to 1 s b. 0.06 to 0.5 microseconds c. 0.2 to 1 milliseconds d. 10 to 100 nanoseconds - ansb. 0.06 to 0.5 microseconds With standard ultrasonic imaging, what happens to the period of a wave as it propagates? a. increases b. decreases c. remains the same - ansc. remains the same What determines the period of an ultrasound wave? a. the transducer b. the medium through which the sound travels c. both a & b d. neither choice a or b - ansa. the transducer Which of the following units are appropriate to describe the period of an acoustic wave? (More than one answer may be correct). a. minutes
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
b. microseconds c. meters d. mm/microseconds e. cubic centimeters - ansa. minutes b. microseconds True or False? The sonographer has the ability to alter the period of an ultrasound wave that is produced by a basic transducer. - ansFalse What term describes the number of cycles that an acoustic variable completes in a second? a. period b. frequency c. pulse repetition period d. variable rate - ansb. frequency Which of the following cannot be considered a unit of frequency? a. per day b. cycles/sec c. Hz d. Hertz e. cycles - anse. cycles What is the range of frequencies emitted by transducers used in ultrasonic imaging? a. 1 to 3 MHz b. 1 to 1000 kHz c. - 10,000 to +10,000 Hz d. 2,000,000 to 15,000,000 Hz - ansd. 2,000,000 to 15,000,000 Hz What establishes the frequency of an ultrasound wave? a. the transducer b. the medium through which the sound travels c. both a & b d. neither choice a or b - ansa. the transducer True or False? With standard ultrasound pulses, the frequency of the ultrasound changes significantly as the wave propagates through the body. - ansFalse When a sonographer increases the maximum imaging depth during an exam, what happens to the frequency? a. frequency increases b. frequency decreases c. remains unchanged - ansc. remains unchanged Ultrasound is defined as a sound with a frequency of ____. A. greater than 20,000 kHz B. less than 1 kHz C. greater than 10 MHz D. greater than 0.02 MHz - ansd. greater than 0.02 MHz Infrasound is defined as sound with a frequency of ______.
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
b. the medium through which the sound travels c. both A and B d. neither choice A or B - ansa. the transducer True or False? With standard diagnostic imaging instrumentation, the sonographer has the ability to vary the amplitude of a sound wave produced by the transducer. - ansTrue As an ultrasound wave travels through the body, its amplitude usually: a. decreases b. increases c. remains the same d. cannot be determined - ansa. decreases Which of the following are acceptable units for the amplitude of an acoustic wave? (More than one answer may be correct). a. cm b. pascals c. gauss d. watts - ansa. cm b. pascals The maximum value of the density of an acoustic wave is 60 lb/in2 while the minimum density is 20 lb/in2. What is the amplitude of the wave? A. 20 lb/in B. 40 lb/in C. 60 lb/in D. none of the above - ansa. 20 lb/in The power of an ultrasound wave can be reported with which of the following units? (More than one answer may be correct). a. watts/square centimeter b. dB/cm c. watts d. kg/cm2 - ansc. watts Typically, as an ultrasound wave travels through soft tissue, the power of the wave: a. decreases b. increases c. remains the same - ansa. decreases True or False? A sonographer can routinely change the power of a wave emitted by a transducer used in diagnostic ultrasonic imaging. - ansTrue Mathematically, when a number is squared, the number is multiplied by: a. 2 b. 0. c. itself d. 1.5 - ansc. itself
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
The final amplitude of an acoustic wave decreases from 27 pascals to 9 pascals. If the initial power in the wave was 27 watts, what is the waves final power? a. 3 watts b. 9 watts c. 1 watt d. none of the above - ansa. 3 watts The final amplitude of an acoustic wave is reduced to one-half its original value. The final power is ____ the original power. a. the same as b. one-half c. double d. none of the above - ansd. none of the above The intensity of an ultrasound beam is defined as the ___ in a beam ___ by the ___ of the beam. a. power, multiplied, diameter b. amplitude, divided, area c. power, divided, area d. amplitude, multiplied, circumference - ansc. power, divided, area As sound travels in the body, what typically happens to the intensity of the wave? a. increases b. decreases c. remains the same - ansb. decreases What are the units of intensity? a. watts b. watts/cm c. watts/cm^ d. dB - ansc. watts/cm^ True or False? With diagnostic ultrasonic imaging instruments, the operator can alter the intensity of an ultrasound beam produced by the transducer. - ansTrue What determines the initial intensity of an ultrasound beam? a. the source of the sound wave b. the medium through which the sound travels c. both A & B d. Neither A or B - ansa. the source of the sound wave What determines the intensity of an ultrasound beam after it has traveled through the body? a. a sound wave's source b. the medium through which the sound travels c. both A & B d. neither A or B - ansc. both the sound wave's source and the medium through which the sound travels What are the units of the transmitted intensity of a sound wave?
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
A sonographer adjusts the output power of the wave emitted by the transducer. Which of the following also changes? (More than one answer may be correct). a. pulse repetition period b. PRF c. propagation speed d. intensity - ansd. intensity The wavelength of a cycle in an ultrasound wave can be reported with which units? a. units of time (sec, min, etc.) b. units of distance (feet, etc.) c. units of area (m^2, etc.) d. mm only - ansb. units of distance (feet, etc.) The wavelength of an ultrasonic wave is determined by: a. the sound source b. the medium through which the wave travels c. both A & B d. neither A or B - ansc. both A & B What is the wavelength of 2MHz sound in soft tissue? a. 0.77mm b. cannot be determined c. 1.54mm d. 2mm - ansa. 0.77mm Which of the following terms best describes the relationship between frequency and wavelength for sound traveling in soft tissue? a. reciprocal b. direct c. related d. inverse - ansd. inverse Two sound pulses travel through the same medium. One waves frequency is 2 MHz and the other is 10 MHz. Which sound wave has a longer period? A. 10 MHz pulse B. 2 MHz pulse C. neither pulse D. cannot be determined - ansb. the 2MHz pulse Two sound pulses travel through the same medium. One waves frequency is 2 MHz and the other is 10 MHz. Which sound wave has a longer wavelength? a. the 10MHz pulse b. the 2MHz pulse c. neither pulse d. cannot be determined - ansb. the 2MHz pulse Two sound pulses travel through the same medium. One waves frequency is 2 MHz and the other is 10 MHz. Which pulse has a lower propagation speed?
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
a. the 10MHz pulse b. the 2MHz pulse c. neither pulse d. cannot be determined - ansc. neither pulse Two sound pulses travel through the same medium. One waves frequency is 2 MHz and the other is 10 MHz. Which pulse has the lowest power? a. the 10MHz pulse b. the 2MHz pulse c. neither pulse d. cannot be determined - ansd. cannot be determined Two sound pulses travel through the same medium. One waves frequency is 2 MHz and the other is 10 MHz. Which pulse has a longer spatial pulse length? a. the 10MHz pulse b. the 2MHz pulse c. neither pulse d. cannot be determined - ansd. cannot be determined True or False? Lower frequency sound creates higher quality images with greater detail. - ansFalse What is the wavelength of 10 MHz sound in soft tissue? a. 0.77mm b. 0.15mm c. 1.54mm d. 10mm - ansb. 0.15mm Two waves, a 5MHz ultrasonic wave and a 5kHz audible wave, travel through soft tissue. T/F: Both the 5MHz and the 5kHz waves travel at similar speeds through the medium. - ansTrue Two waves, a 5MHz ultrasonic wave and a 5kHz audible wave, travel through soft tissue. T/F: The period of the 5 MHz wave is less than the period of the audible wave. - ansTrue Two waves, a 5MHz ultrasonic wave and a 5kHz audible wave, travel through soft tissue. T/F: The wavelength of the 5 MHz wave is greater than the 5 kHz wave. - ansFalse Two waves, a 5MHz ultrasonic wave and a 5kHz audible wave, travel through soft tissue. T/F: The ultrasound wave travels much faster than the audible wave. - ansFalse The ultrasound pulse propagates from soft tissue through a mass. Sound's propagation speed in the mass is 1,575 m/s. T/F: The frequency of the wave increases as it travels through the mass. - ansFalse The ultrasound pulse propagates from soft tissue through a mass. Sound's propagation speed in the mass is 1,575 m/s. T/F: The period of the sound wave decreases as it travels through the mass. - ansFalse The ultrasound pulse propagates from soft tissue through a mass. Sound's propagation speed in the mass is 1,575 m/s. T/F: The wavelength increases while the wave travels through the mass. - ansTrue
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
A. higher than B. lower than C. equal to D. cannot be determined - ansa. higher than Compared to soft tissue, the speed of an acoustic wave through lung tissue is _____. A. faster B. slower C. equal D. cannot be determined - ansb. slower What is the best estimate for the speed of sound in a tendon? a. 1,000 m/s b. 1,540 m/s c. 1,754 m/s d. 5,400 m/s - ansc. 1,754 m/s As a general rule, which of the following lists media in increasing order of propagation speeds? a. gas, solid, liquid b. liquid, solid, gas c. solid, liquid, gas d. gas, liquid, solid - ansd. gas, liquid, solid What is the speed of sound in air? a. 1,540 m/s b. 330 m/s c. 100 m/s d. 3,010 m/s - ansb. 330 m/s True or False? Soft tissue is an imaginary construct that actually does not exist. - ansTrue What is the propagation speed of a 5 megahertz sound wave in soft tissue? a. 1,450 m/s b. 1,540 km/s c. 1.54 m/s d. 1.54 mm/microsecond - ansd. 1.54 mm/microsecond If sound travels at exactly 1,540 m/sec in a particular medium, then the medium ____. A. must be soft tissue B. may be soft tissue C. cannot be soft tissue - ansb. may be soft tissue If sound doesn't travel at 1,540 m/s in a medium, then the medium ____. A. must be soft tissue B. may be soft tissue C. cannot be soft tissue - ansc. cannot be soft tissue The propagation speeds of ultrasound waves in muscle, liver, kidney, and blood are ______. a. exactly the same
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
b. very similar to each other c. vastly differen - ansb. very similar to each other The speed at which a wave travels through a medium is determined by: a. the sound wave's properties only b. the medium's properties only c. properties of both wave and medium d. none of the above - ansb. the medium's properties only What two properties establish sound's propagation speed in a given medium? a. elasticity and stiffness b. stiffness and impedance c. conductance and density d. density and stiffness - ansd. density and stiffness The characteristics of four media are described below. Which if the media has the slowest propagation speed? a. high density and high elasticity b. low density and high stiffness c. low stiffness and low density d. low compressibility and low stiffness - ansa. high density and high elasticity Compressibility describes a characteristic of a medium. Which two terms describe the same property as compressibility? a. density and stiffness b. density and conductance c. stiffness and elasticity d. elastance and impedance - ansc. stiffness and elasticity When the elasticity of a medium is high, the ____ is high. a. stiffness b. propagation speed c. compressibility d. reflectivity - ansc. compressibility Two sound waves with frequencies of 5 and 3 MHz travel to a depth of 8 cm in a medium and then reflect back to the surface of the body. Which acoustic wave arrives first at the surface of the body? A. the 5 MHz wave B. the 3 MHz wave C. neither D. cannot be determined - ansc. neither What are the units of pulse duration? a. units of frequency (Hz) b. msec only c. units of time (sec, year) d. units of distance (feet) - ansc. units of time
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
c. both A & B d. neither A or B - ansc. both A & B Which of the following best describes the spatial pulse length? a. frequency multiplied by wavelength b. PRF multiplied by the wavelength c. wavelength multiplied by the number of cycles in the pulse d. duty factor mutliplied by the wavelength - ansc. wavelength multiplied by the number of cycles in the pulse Two transducers send ultrasound pulses in soft tissue. One transducer emits sound with a 4MHz frequency, and the other produces sound at a 6MHz frequency. Each pulse contains 4 cycles. Which has a greater spatial pulse length? a. the 6MHz pulse b. the 4MHz pulse c. they are the same d. cannot be determined - ansb. the 4MHz pulse Using a specific transducer, what happens to the spatial pulse length as the sonographer increases the maximum imaging depth? a. increases b. decreases c. remains the same d. cannot be determined - ansc. remains the same True or Fals? While imaging soft tissue, the spatial pulse length does not change as long as the components of the ultrasound system are the same. - ansTrue On what does the pulse repetition period depend? a. the source of the sound wave b. the medium through which the pulse travels c. both A and B d. neither A or B - ansa. the source of the sound wave A sonographer adjusts the maximum imaging depth of an ultrasound system. Which of the following also changes? (More than one answer may be correct). a. pulse repetition period b. wavelength c. pulse repetition frequency d. frequency - ansa. pulse repetition period c. pulse repetition frequency Which of the following correctly describes pulse repetition period? a. the production of the wavelength and propagation speed b. the reciprocal of the frequency c. the sum of the pulse's "on" time and the listening "off" time d. the time that the transducer is pulsing - ansc. the sum of the pulse's "on" time and the listening "off" time
Physics in the Fourth Edition.
A Guide for Professionals
Understanding Ultrasound Physics
Fourth Edition - Edelman
What happens to the pulse repetition period if the sonographer decreases the maximum imaging depth achieved in an ultrasound scan? a. increases b. decreases c. remains the same d. cannot be determined - ansb. decreases Two ultrasound systems, one producing sound with a frequency of 3MHz and the other at 6MHz, are used to image a patient. The maximum imaging depths of both exams is 8cm. T/F: The period of the 3MHz sound is greater than the period of the 6MHz sound. - ansTrue Two ultrasound systems, one producing sound with a frequency of 3MHz and the other at 6MHz, are used to image a patient. The maximum imaging depths of both exams is 8cm. T/F: The wavelength of the 3MHz ultrasound is greater than the 6MHz sound. - ansTrue Two ultrasound systems, one producing sound with a frequency of 3MHz and the other at 6MHz, are used to image a patient. The maximum imaging depths of both exams is 8cm. T/F: The pulses produced by both systems travel at the same speed in the patient. - ansTrue Two ultrasound systems, one producing sound with a frequency of 3MHz and the other at 6MHz, are used to image a patient. The maximum imaging depths of both exams is 8cm. T/F: The PRF of the 6MHz transducer is greater than the PRF of the 3MHz transducer. - ansFalse The maximum imaging depth during an exam is unchanged. A new transducer with a longer pulse duration is used. T/F: The pulse repetition period is increased. - ansFalse The maximum imaging depth during an exam is unchanged. A new transducer with a longer pulse duration is used. T/F: The pulse repetition frequency is increased. - ansFalse The maximum imaging depth during an exam is unchanged. A new transducer with a longer pulse duration is used. T/F: The duty factor is increased. - ansTrue The maximum imaging depth during an exam is unchanged. A new transducer with a longer pulse duration is used. T/F: The frequency is increased. - ansFalse What are the units of pulse repetition frequency (PRF)? a. seconds b. 1/seconds c. mm/microseconds d. seconds^- 2 - ansb. 1/seconds (same as hertz) The pulse repetition frequency of ultrasound produced by a transducer typical of diagnostic imaging systems _________. a. can be changed by the sonographer b. depends on the medium through which the sound travels c. is unchanged as long as the same ultrasound system is used d. has nothing to do with the clinical imaging - ansa. can be changed by the sonographer In diagnostic imaging, what establishes the pulse repetition frequency? a. the source of the sound b. the medium through which the sound travels c. both A and B
