DMS 209 Review Book Chapter 1 Questions

An increase in PRF would lead to: A. An increase in DF B. A decrease in PD C. An increase in the number of cycles D. A decrease in resolution

A. An increase in DF

As a sound wave travels through the human body, the intensity of the sound wave decreases as a result of: A. Attenuation B. Elevational resolution C. Huygen's principle D. Refraction

A. Attenuation

Areas of high pressure and density are referred to as: A. Compressions B. Rarefactions C. Diffractions D. Refraction

A. Compressions

Which of the following is determined by the sound source only? A. Frequency B. Wavelength C. SPL D. Propagation speed

A. Frequency

Density and propagation speed are: A. Inversely related B. Directly related C. Directly proportional D. Unrelated

A. Inversely related

Density is typically measured in: A. Kilograms or centimeter cubed B. Millimeters C. Watts per square centimeter D. Pascals

A. Kilograms or centimeter cubed `

Micro denotes: A. Millionth B. Hundredth C. Million D. Billionth

A. Millionth

The attenuation coefficient in soft tissue is equal to: A. One-half of the operating frequency B. Double the operating frequency C. Frequency times path length D. The total decibels

A. One-half of the operating frequency

What time is defined as the beginning of one pulse to the beginning of the next pulse and, therefore, includes both the "on" and "off" time? A. PRP B. PD C. DF D. PRF

A. PRP

Which of the following is described as the ability of an object to resist compression and relates to the hardness of a medium? A. Stiffness B. Density C. Pressure D. Inertia

A. Stiffness

The typical range of frequency for diagnostic ultrasound imaging is: A. 20 to 20,000 Hz B. 1 to 20 MHz C. 2 to 15 kHz D. 12 to 100 MHz

B. 1 to 20 MHz

What is the total amount of attenuation that occurs if a 6.0-MHz sound bean travels through 4 cm of soft tissue? A. 24 dB B. 12 dB C. 6 dB D. 1.5 dB

B. 12 dB

If the angle of incidence is 40°, what is the angle of transmission at the interface if medium 1 has a propagation speed of 1320 m/s and medium 2 had a propagation speed of 1700 m/s? A. 0° B. >40° C. <40° D. Cannot tell the angle of transmission

B. >40°

Which of the following would have the highest propagation speed? A. Air B. Bone C. Soft tissue D. Water

B. Bone

The prefix "centi" denotes: A. Thousandths B. Hundredths C. Millions D. Hundreds

B. Hundredths

As imaging depth increases, PRP: A. Remains constant B. Increases C. Decreases D. Doubles

B. Increases

What is the change in intensity if the power decreases by half? A. Intensity density B. Intensity is halved C. Intensity is one-fourth D. Intensity does not change

B. Intensity is halved

All of the following are true of wavelength except: A. It is determined by both the medium and the sound source B. It is equal to the period divided by the frequency C. It is inversely related to frequency D. It is directly related to period

B. It is equal to the period divided by the frequency

Pressure is typically expressed in: A. Frequency B. Pascals C. Decibels D. Kilograms per centimeter cubed

B. Pascals

What are units for pressure? A. Feet, inches, centimeters, or miles B. Pascals or pounds per square inch C. Kilograms per centimeter cubed D. Hertz, kilohertz, or megahertz

B. Pascals or pounds per square inch

All of the following relate to the strength of the sound wave except: A. Amplitude B. Wavelength C. Intensity D. Power

B. Wavelength

Adding damping to the transducer improves which type of resolution? A. Transverse resolution B. Temporal resolution C. Axial resolution D. Elevation all resolution

C. Axial Resolution

The recent age of time that the ultrasound system is producing pulses of ultrasound describes the: A. PRP B. PD C. DF D. PRF

C. DF

As imaging depth increases, the PRF must: A. Not change B. Increase C. Decrease D. PRF does not relate to imaging depth

C. Decrease

The inertia of the medium describes is: A. Attenuation coefficient B. Stiffness C. Density D. Elasticity

C. Density

Transducers have material within them that, when electronically stimulated, produces ultrasound waves. This is most likely some form of: A. Tungsten acetate B. Dilithium zirconium C. Lead zirconate titanate D. Barium sulfate

C. Lead zirconate titanate

SPL can be calculated by: A. Multiplying the number of cycles by the frequency B. Dividing the period by the frequency C. Multiplying the number of cycles by the wavelength D. Dividing the number of cycles by the wavelength

C. Multiplying the number of cycles by the frequency

Which of the following is defined as the number of ultrasound pulses emitted in 1 second? A. PRP B. DF C. PRF D. SPL

C. PRF

The change in the direction of the original sound wave that occurs when sound interacts with two different tissue types that have a different propagation speed is referred to as: A. Wavelength B. Scattering C. Refraction D. Absorption

C. Refraction

In clinical imaging, the wavelength typically measures between: A. 1 and 10 Hz B. 1540 and 2000 m/s C. 0 and 1 D. 0.1 and 0.8 mm

D. 0.1 and 0.8

Which of the following would have the lowest propagation speed? A. Water B. Soft tissue C. Bone D. Lung tissue

D. Lung tissue

Which of the following is defined as only the active time? A. DF B. PRF C. period D. PD

D. PD

Which of the following describes the amount of refraction that occurs at an interface? A. Bernoulli's law B. Poiseuille's law C. Law of reflection D. Snell's law

D. Snell's law

What are the units of DF? A. dB B. dB/cm C. Hz D. Unitless

D. Unitless

Which of the following is described as the distance over which one cycle occurs? A. PD B. DF C. Period D. Wavelength

D. Wavelength

Which of the following is determined by the sound source and medium? A. Propagation speed B. Frequency C. Period D. Wavelength

D. Wavelength

All of the following are true of power except: A. As amplitude increases, power remains the same B. Power is proportional to amplitude squared C. Intensity is proportional to power D. Power is measured in milliwatts

A. As amplitude increases, power remains the same

Which of the following is an appropriate unit of measurement for propagation speed? A. Millimeters per microsecond (mm/μs) B. Watts per square centimeter (W/cm^2) C. Microseconds (ms) D. Kilohertz (kHz)

A. Millimeters per microsecond (mm/μs)

Damping of the sound beam: A. Reduces the SPL B. Increases the SPL C. Increases the PD D. Has no impact on SPL or PD

A. Reduces the SPL

The DF for CW ultrasound is: A. 1.0% B. 100% C. 20,000 Hz D. 8 Pa

B. 100%

The major component of attenuation is: A. Scatter B. Absorption C. Transmission D. Refraction

B. Absorption

Which of the following requires an oblique interface and a propagation speed mismatch? A. Reflection B. Refraction C. Normal incidence D. Damping

B. Refraction

What term is defined as "the power if a wave divided by the areas over which the power is distributed?" A. Amplitude B. Power C. Intensity D. Absorption

C. Intensity