Test 11 1. The following are true about the ultrasound:a. impedance is measured in grams / cm 2 /sec2. The following are true about the velocity of ultrasound:
b. the closer the beam to the right angle the less the sound is reflected
c. attenuation of ultrasound results in heating of tissues
d. A-mode ultrasonography is displayed as a series of spikes
e. B-mode ultrasonography is displayed as a series of spikesa. it is dependent on the frequency3. In ultrasound:
b. is faster through the soft tissue than the skull
c. is faster through the silicone oil than the vitreous
d. is about 1540 meters per second through the soft tissue
e. is proportional to the compressibility of the medium through
which the sound travelsa. impedance determines the proportion of sound energy reflected4. The following are true about ultrasound:
and transmitted at an interface.
b. the size of a pulse generated in an A-scan is a measure of the
intensity of the reflected ultrasonic echo.
c. the sound travels poorly through air.
d. the velocity is faster through a denser materials.
e. the velocity is dependent on the temperature of the material through
which it travels.a. it is produced by a piezoelectric crystals.
b. the frequency of a sound wave is inversely related to its wavelength
c. ultrasound is a longitudinal wave form
d. ultrasound can be refracted
e. ultrasound can be focused5. In ultrasound:a. the acoustic impedance of a material is the product of its density
and the velocity of sound within it
b. acoustic impedance determines beam refraction
c. as the angle of incidence increases less sound is reflected
d. a thicker piezoelectric crystal has a lower resonance frequency
e. a thicker piezoelectric crystal has a longer wavelength.
Return to the main page