Exam 2: Ultrasound

If the impedances are equal between two media in perpendicular incidence,there is no ________.

Duty factors for sonography are typically in the range of ________%.

If the beam area decreases,the intensity ________.

For each centimeter of distance,the pulse round-trip travel time is equal to ________.

What would be the frequency for a 0.22 mm wavelength in soft tissue?

Contrast agents produce echoes because the impedance of the suspended particles is similar to the suspending medium.

The best way to describe the role of ultrasound reflection and scattering in diagnostic imaging is it ___________________.

The average propagation speed in soft tissue is 1.54 mm/µs.

The ultrasound machine directly measures distance.

Sound is a mechanical longitudinal wave.

Stiffer media have ________ sound speeds.

Pulsed ultrasound consists of ________ separated by ________ of time.

Impedance is equal to density multiplied by ________.

Attenuation increases with an increase in wavelength.

If intensity reflection coefficient increases,intensity transmission coefficient ________.

For perpendicular incidence and equal impedances between media,there is no ________ and the ________ intensity equals the incident intensity.

If the pulse duration is 3 µs and the pulse repetition period is 350 µs,the duty factor would be ________ %.

A continuous wave (CW) sinusoidal wave is characterized by multiple frequencies.

Interfaces that scatter ultrasound energy are usually considered those that are equal to or smaller than the wavelength.

In oblique incidence,when the propagation speeds on either side of the boundary are different,which incidence is most likely to occur?