CTCM Test A

Edelmen's SPI Exam Review




Sound waves are:
a) electric
b) mechanical, transverse
c) spectral
d) longitudinal, mechanical -CORRECT ANSWERD

The speed of sound of ultrasound in soft tissue is closest to:
a) 1,540 km/sec
b) 1.54 km/sec
c) 1,500 m/s
d) 1,540 mm/sec -CORRECT ANSWERC

Which is not an acoustic variable?
a) density
b) pressure
c) distance
d) intensity -CORRECT ANSWERD

The effects of soft tissue on ultrasound are called:
a) acoustic proliferation properties
b) dynamic effects
c) acoustic propagation properties
d) biological effects -CORRECT ANSWERC

All of the following are true EXCEPT:
a) two waves with identical frequencies must interfere constructively.
b) constructive interference is associated with waves that are in-phase.
c) out-of-phase waves interfere destructively.
d) waves of different frequencies may exhibit both constructive and destructive
interference at different times. -CORRECT ANSWERA

,Put in decreasing order:
a) deca
b) deci
c) micro
d) centi -CORRECT ANSWERabdc

______ is the time to complete one cycle
a) pulse duration
b) pulse period
c) period
d) duration period -CORRECT ANSWERC

Which of the following sound waves is ultrasonic and least useful in diagnostic imaging?
a) 30 KHz
b) 8 Mhz
c) 8,000 Hz
d) 3,000 Hz
e) 15 Hz -CORRECT ANSWERA

______ is the distance covered by one cycle.
a) pulse length
b) wavelength
c) cycle distance
d) cycle duration -CORRECT ANSWERB

Which of the following is determined by the source and the medium?
a) frequency
b) period
c) propagation speed
d) range resolution -CORRECT ANSWERD

Propagation speed = _______ x wavelength
a) pulse duration
b) period
c) # of cycles in the pulse
d) frequency -CORRECT ANSWERD

As a result of _____ the propagation speed increases.
a) increasing stiffness and increasing density
b) increasing stiffness and increasing elasticity

,c) decreasing compressibility and decreasing density
d) decreasing stiffness and decreasing density. -CORRECT ANSWERC

Put in decreasing order of propagation speed.
a) gas
b) liquid
c) solid -CORRECT ANSWERc b a

If the frequency of an ultrasound wave is doubled, what happens to the period?
a) doubles
b) halved
c) remains the same
d) 4x greater -CORRECT ANSWERB

The units of pulse repetition frequency are:
a) per minute
b) microseconds
c) mm/microseconds
d) MHz -CORRECT ANSWERA

The time from the beginning of the pulse to the end of that pulse is _______?
a) period
b) pulse duration
c) pulse length
d) PRF -CORRECT ANSWERB

What happens to the speed of sound in a medium when the bulk modulus increases?
a) faster
b) slower
c) unchanged -CORRECT ANSWERA

_________ resolution is determined by the spatial pulse length
a) radial
b) image
c) axial
d) angular -CORRECT ANSWERA or C

If the wave's amplitude is doubles, what happens to the power?
a) nothing
b) halved
c) doubled

, d) quadrupled -CORRECT ANSWERD

If the level of acoustic variable ranges from 55-105, what is the amplitude?
a) 105
b) 50
c) 25
d) 55 -CORRECT ANSWER25

Power of sound has units of:
a) dB
b) dB/cm
c) watts
d) watts/cm^2 -CORRECT ANSWERC

If the intensity of a sound beam remains unchanged while the beam area is reduced in
half, what has happened to the power?
a) quadrupled
b) doubled
c) halved
d) unchanged -CORRECT ANSWERC

Which of these intensities is the smallest?
a) SATP
b) SPTP
c) SATA -CORRECT ANSWERC

The duty factor for CW ultrasound is
a) 10.0
b) 1%
c) 1.0
d) 0.0% -CORRECT ANSWERC

What is the minimum value of the duty factor? a) 10.0
b) 1%
c) 1.0
d) 0.0% -CORRECT ANSWERD

What are the units of intensity?
a) watts
b) dB
c) watts/cm^2