Sono 112 Chpt. 3

Normal incidence implies that the incident beam direction is _____ to the media interface.

Fluids absorb less sound energy than tissue.

An area with no echogenicity can also be described as anechoic.

If two media have identical acoustic impedance, all of the sound energy will be reflected.

When sound strikes a boundary at the "critical angle" none of the energy transmits to media 2.

_____ is the conversion of acoustic energy from a sound wave into heat within the body.

Structure that are large relative to the wavelength and possess a smooth surface are described as _______.

______ is the dominant form of attenuation in soft tissue.

›In soft tissue, what is the total attenuation of a 5 MHz ultrasound beam traveling to a depth of 10 cm?

Which type of attenuation refers to the "bending" of a beam at an interface between 2 media?

When imaging specular reflectors, the incident angle is _______ the angle of reflection.

Which of the following laws describes the physics of refraction?

The greater the acoustic impedance mismatch, the weaker the reflection will be.

Attenuation is ____ to frequency and depth of imaging.

______ is directly related to frequency⁴ and occurs when the reflector is very small relative to the wavelength.

Unless imaging very superficial blood flow, low frequencies should be used to perform Doppler.

______ will occur if there is a non-perpendicular incident angle and differing propagation speeds.

If sound travels from a media with a fast propagation speed to a media w/ a slow speed, the ____ angle will be largest.

If the power of a sound beam is increased from 100 Watts to 1000 Watts, what is the increase in decibels?

The purpose of the gel when imaging is to reduce the acoustic impedance mismatch between the transducer crystal and skin

For normal incidence, the amount of reflection is determined by the:

_____ is the weakest form of reflection.

If the transmit voltage is doubled, what is the increase measured in decibels?

In soft tissue, less than 1% of the incident ultrasound energy is transmitted at a soft tissue boundary.

The equation Z= p x c is used for determining the: