How much bigger is one billion than one thousand ?
A. 1,000
B. 1,000,000
C. 10 times
D. 10,000 ANS: B. 1,000,000 Times
Select the sequence that appears in increasing order.
A. mega, kilo, hecto, milli, giga
B. nano, milli, micro, deci, deca, mega
C. centi, deci, deca, hecto
D. milli, hecto, centi, deci, nano, giga ANS: C. Centi, deci, deca, hecto
How many nanoseconds are in 7 seconds ?
A. 7,000,000
B. 7,000,000,000
C. 7 million
D. 0.0000007 ANS: B. 7,000,000,000
The letters below represent the abbreviations for the prefixes of the metric system. Select the sequence
that appears in decreasing order .
A. m, k, M, g, da
B. g, m, k,d, microseconds
,C. g, k, di, m, microseconds, n
D. M, k, da, d, c ANS: D. M, k, da, d, c
What term is the reciprocal of Mega ?
A. nano
B. kilo
C. macro
D. micro ANS: micro
As sound travels through a medium, what term describes the effects of the medium on the sound wave
?
A. toxic effects
B. acoustic propagation properties
C. bioeffects
D. transmission properties ANS: B. acoustic propagation properties
Which of the following is true of all waves ?
A. they travel through a medium
B. all carry energy from one site to another
C. their amplitudes do not change
D. they travel in a straight line ANS: B. all carry energy from one site to another
Which of the following types of waves do not require a medium in order to propagate ?
,A. light
B. heat
C. sound
D. television ANS: A. light, B, heat, and D. television
Using a specific transducer, what happens to the spatial pulse length as the Sonographer increases the
maximum imaging depth?
A. Increases
B. Decreases
C. remains the same
D. Cannot be determined ANS: C. The spatial pulse length is determined by the number of cycles in the
pulse and the wavelength of each cycle. With the same system, These factors are unchanged. and spatial
pulse length remains the same.
Which of the following are acoustic variables ?
Frequency, pressure, propagation speed, wavelength, voltage, intensity, motion of particles in the wave,
density ANS: Pressure, motion of particles in the wave, density
True or false ? While imaging soft tissue, the spatial pulse length does not change as long as the
components of the ultrasound system are the same. ANS: True. The overall length of a pulse is equal to
the wavelength multiplied by the number of cycles in a pulse. Using a particular ultrasound system and
transducer, the pulse length cannot change.
Sound can be characterized as:
A. energy flowing through a vacuum
, B. a variable
C. cyclical oscillations in certain variables
D. a principle of acoustics ANS: C. cyclical oscillations in certain variables
What are the units of measurement for Pressure ?
A lb/in^3
B. F
C miles
D. Pa
E cm
F. lb/in^2
G. kg/m^3 ANS: D. Pa and F. lb/in^2
What are the units of measurement for Density ?
A lb/in^3
B. F
C miles
D. Pa
E cm
F. lb/in^2
G. kg/m^3 ANS: A. lb/in^3 and G. kg/m^3
What are the units of measurement for Particle motion?