conversions
convert 8MHz to Hz
8,000,000 Hz
convert 86 mm to cm
8.6 cm
what do waves transfer from one location to another?
energy
name the lowest intensity
Spatial average temporal average (SATA)
What is the relationship between PRF and PRP
inversely (reciprocals)
convert 10cm to mm
100mm
what is the reciprocal of 5
1/5
or
.2
define frequuency
cycles per second
3dB of attenuation means WHAT decrease in intensity?
intensity if halved
the unitless fraction of time that pulsed ultrasound is on
duty factor
convert 6 mm to cm
60 cm
What is the reciprocal of x
1/x
Define wavelength
the DISTANCE over which one cycle occurs
what is the attenuation rate in soft tissue?
.5dB/cm/MHz
what is the duty factor of CW ultrasound?
100%
express 1/4 as a decimal
.25
what is the reciprocal of period
what is the typical speed of sound in soft tissue?
1.54 mm/µs
or
1540 m/s
Name the causes of attenuation.
Which factor is responsible for the majority of attenuation in soft tissue
scattering, absorption, reflection
ABSORPTION is dominant
Pulse duration equals
Period X the number of cycles in a pulse
convert 10,000,000 Hz to kHz AND MHz
10,000 kHz
10MHz
what is the reciprocal of 1/6
6
As sound travels, the reduction in amplitude and intensity of the wave is called ___
attenuation
a decibel (dB) is proportional to
the RATIO of two sound intensities
What is the pulse duration of a four-cycle pulse in a period of 0.5 µs
2.0 µs