with complete solutions
What is frequency determined by? CORRECT ANSWERS: The source, thickness of piezoelectric element and propagation speed to a lesser degree
Thicker element is equal to ________ frequencies CORRECT ANSWERS: Lower
What is the reciprocal of frequency and what is the symbol CORRECT ANSWERS: Period, T
The time it takes for 1 cycle to occur CORRECT ANSWERS: Period
What is propagation speed determined by CORRECT ANSWERS: Stiffness and density of the medium
Propagation speed of sound through soft tissue CORRECT ANSWERS: 1,540 m/s
Increasing the stiffness of a tissue does what to the propagation speed? CORRECT ANSWERS: Increases
Increasing the density of a tissue does what to the propagation speed? CORRECT ANSWERS: Decreases
Propagation speed of tissues from slowest to fastest CORRECT ANSWERS: Air, fat, water, liver, blood, muscle, bone
What is the distance over which one cycle occurs? CORRECT ANSWERS: Wavelength
What happens to frequency when you increase the wavelength? CORRECT ANSWERS: Decreases
What is the wavelength symbol CORRECT ANSWERS: Lambda
What is the wavelength equation? CORRECT ANSWERS: Propagation speed divided by the frequency
Units of wavelength CORRECT ANSWERS: Mm, m, km
What is wavelength determined by? CORRECT ANSWERS: Source and medium
What describes the strength of the sound wave? CORRECT ANSWERS: Amplitude
What happens to a beam as it travels? CORRECT ANSWERS: Decreases in amplitude and intensity due to attenuation What does amplitude represent on the chart of a wave? CORRECT ANSWERS: The height of a vibration
What does pascals measure? CORRECT ANSWERS: Pressure amplitude
What happens to amplitude when you increase depth? CORRECT ANSWERS: Decreases due to attenuation
What is amplitude determined by? CORRECT ANSWERS: The source
Related to strength of the beam CORRECT ANSWERS: Power
What is the unit for power? CORRECT ANSWERS: Watts
What is power proportional to? CORRECT ANSWERS: Amplitude squared
Relates to strength of beam and represents the concentration of energy in beam CORRECT ANSWERS: Intensity
What is the equation and unit for intensity CORRECT ANSWERS: Power/area, W/cm squared
What is acoustic resistance to sound in a medium? CORRECT ANSWERS: Impedance
What is the equation for impedance? CORRECT ANSWERS: Density times propagation speed
What is impedance determined by and what are the units? CORRECT ANSWERS: The medium, rayls
The bigger the mismatch, the stronger CORRECT ANSWERS: The reflection and brighter the dot
What is the number of pulses that occur in one second? CORRECT ANSWERS: Pulse repetition frequency
What is the unit of PRF? CORRECT ANSWERS: Hertz
How is the PRF changed? CORRECT ANSWERS: By changing depth
What would decrease the PRF? CORRECT ANSWERS: Increasing depth
What is the reciprocal of of pulse repitition frequency? CORRECT ANSWERS: Pulse repetition
period
What is the time it takes for one pulse to occur? CORRECT ANSWERS: Pulse repetition period