Physics Boards Review Part 1

What type of medium has has the highest absorption coefficient? (air, bone, or soft tissue(water)

The propagation speed is fastest in? (soft tissue, bone or air)?

For soft tissue, if the path length is doubled, total attenuation will:

If the attenuation coefficient for muscle is 5.0 dB at 3MHz, what is the attenuation coefficient at 6MHz?

The portion of sound energy redirected towards the sound source is called:

If the acoustic output is set at 0 dB, this indicates:

If the half value layer thickness for muscle is 4cm at 2MHz, the HVL thickness at 4MHz is ___cm.

If the amplitude is increased by a factor of 2, intensity:

The maximum pressure variation that occurs in a cycle is termed:

An ultrasound field in soft tissue experiences an intensity reduction of 9 dB. This is equivalent to ____ Half Intensity Depth(s).

The tissue property that determines the amount of refraction at an interface is:

If the reflection intensity coefficient at an interface is 25%, what is the transmission intensity coefficient?

Acoustic impedance is equal to:

The propagation speed through the medium is NOT dependent on:

If the initial intensity is reduced to 25%, this is equivalent to ____ dB.

Which of the following is an example of a specular reflector?

If the acoustic power is doubled, intensity will:

If the wavelength is decreased by 1/4 , the frequency will:

What is the typical transmission coefficient at a soft tissue/air interface?

As the temperature decreases, the propagation speed in tissues would:

If the total attenuation at 2 MHZ = 20 dB, the total attenuation at 4 MHz is ____ dB.

Which of the following accounts for the greatest portion of the attenuation rate at an air/soft tissue interface?

Which of the following types of media would have the highest characteristic acoustic impedance value?

Decreasing the beam area to 1/6 of the original will result in:

Which of the following conditions is most likely to produce the greatest amount of refraction? (0 degrees = normal incidence)

If the wavelength for a sound field = 2 mm, which of the following interfaces would most likely behave as a specular reflector?

If the wavelength for a sound field is 1 mm, which of the following reflectors would behave as a non-specular reflector?

If the transmission coefficient is 60% at an interface, the reflection coefficient is:

Which of the following would have the lowest absorption coefficient?

Which of the following mediums would have the largest half intensity depth in cm?

The sonographic pattern displayed distal to a region with a low attenuation rate is termed:

What is the typical per cent reflection at a muscle/bone interface?

Which of the following factors accounts for the greatest portion of the attenuation rate in soft tissue?

If the acoustic output is increased by 9 dB, the resulting intensity has increased by a factor of:

The theory/principle that relates the angle of incidence to the angle of refraction is:

A large amplitude pulse (voltage) from the pulser results in:

Which control changes the intensity of the transmitted pulse?

Increasing the pulse repetition frequency will:

The primary method that the sonographer uses to control frame rate during real time imaging is:

The initial amplitude is determined by :

According to the range equation, which of the following are required to calculate the distance to the reflector?

The signal processing function that eliminates the negative component of the signal is termed:

The System Gain function is performed in the:

Reflector B is twice the distance from the transducer as reflector A. It takes ______ times as long for an echo to arrive from reflector B as from reflector A.

The sonographer has increased the size of the sector width to image a large mass. What can the sonographer do to maintain the same temporal resolution before this adjustment?

Increasing the number of scan lines per frame improves:

If the gain is increased by 9 dB, the power has been increased by a factor of:

Adjusting the TGC controls affects the settings in the:

Which of the following transducer arrays utilizes electronic beam steering?

On an A-Mode display, the height of the spike represents:

The computer parameter that limits the number of gray levels available to display on the image matrix is:

Which of the following system components generates the signals to focus and steer the sound field?

The pulse repetition period is the reciprocal of:

In cardiac imaging, reducing the size of the sector angle will:

The ability to distinguish between adjacent structures producing echo amplitudes of similar amplitude is termed:

The typical dynamic range in the amplifier is:

What is the maximum number of displayed shades of gray in a 7-bit processor?

Which of the following digital scan converters would display the best contrast resolution?

In which of the following modes is time the unit of measurement on one axis?

How many levels of information can a single bit represent?

Preprocessing programs are performed in the:

Postprocessing programs are performed in the:

The use of cine loop will primarily improve _________ resolution

During real time imaging, if the scan line density is reduced to 1/4, the maximum frame rate is:

In clinical applications, maximum reflection amplitude occurs with:

At a muscle/fat boundary, the percentage of sound energy reflected will be:

As sound propagates through the medium, amplitude:

As frequency increases, half intensity depth:

Propagation speed is determined by the:

By altering the imaging depth, the period of the wave:

At a soft tissue/air interface, the percentage of sound transmitted will be:

Determine the power if the amplitude of the wave is 4.

The _______ is a unit of measurement used to express the difference or ratio between two variables.

The sonographer can change the sound field intensity by manipulating:

For soft tissue, which of the following would most likely be used to represent a 50% reduction in intensity?

The total attenuation for a 10 MHz sound field in soft tissue at 2 cm is _____ dB.

Increasing intensity increases

At soft tissue interfaces, the percentage of ultrasound energy transmitted is approximately _____ %,

Which of the following has an average propagation speed of 1.54 mm/µs?

As sound propagates through the medium, intensity:

Frequency is determined by the:

The best example of a Rayleigh scatterer is:

The initial amplitude is determined by :

As propagation speed and density values increase, acoustic impedance:

Determine the attenuation coefficient in dB/cm for a 10 MHz sound field in soft tissue.

The attenuation rate will increase if there is an increase in:

A region of high pressure, high density is:

Wavelength is determined by the:

To maximize reflection from a specular reflector, the sonographer should strike the interface at ______ degrees.

This artifact cannot occur at perpendicular incidence

As sound propagates through a medium, power:

A sound beam's wavelength is 0.5 mm. Which of the following would be an example of a nonspecular reflector?

Impedance is equal to:

For an unfocused circular soundfield, the crystal diameter is 30 mm. What is the beam diameter in mm at a depth equal to twice the near field length?

Elevational resolution is related to:

The intensity of a focused beam is generally:

The product of the period and the number of cycles in the pulse is:

Axial resolution can be improved by using:

The type of real-time transducer that employs a combination of electronic focusing and mechanical steering is:

The reverse piezoelectric effect is best described as:

Which of the following transducers would be most useful for imaging superficial structures?

Lateral resolution is equal to:

The unit of measurement for the duty factor is:

Increasing the pulse repetition period:

For an unfocused sound field utilizing a 10 mm crystal diameter, the sound field diameter at the end of the near field will be ____ mm.

Grating lobes in electronic array systems:

As frequency increases, the beam width will:

The principle that states that all points on a wavefront can be considered as point sources for the production of spherical secondary wavelets was postulated by:

The ____ relates the bandwidth to operating frequency

For an unfocused circular sound field, the crystal diameter is 40 mm. What is the beam diameter 1cm from the crystal surface in mm?

The piezoelectric properties of the transducer will be lost if the crystal is heated above the:

What is the most commonly used material for ultrasound transducer crystal elements?

A decreased pulse duration produces:

The beam of an unfocused transducer diverges where?

The amount of divergence in the far field can be decreased by:

The near field length of an unfocused transducer depends on:

Extraneous sound energy emitted from a linear sequenced array are called:

The spatial pulse length:

Transmit delay focusing in a linear array transducer will improve:

Axial resolution depends on the ______

The damping material will improve

For a given sound field, which of the following would demonstrate the lowest intensity value?

What type of tissue is most susceptible to the effects of cavitation?

With all other parameters constant, increasing the acoustic output will:

Which artifact is associated with reverberation and resonance in a small gas bubble or surgical staple?

Which control changes the intensity of the transmitted pulse?

Increasing the number of scan lines per frame improves:

The use of cine loop will primarily improve _________ resolution

What system component generates the signals to focus and steer the sound field?