ARDMS SPI 500.docx

A sound wave is - correct answer mechanical, longitudinal A compression area of a sound wave is - correct answer high pressure, high density A rarefaction area of a sound wave is - correct answer low pressure, low density Which is considered an acoustic variable - correct answer pressure Which is a unit for pressure - correct answer N/m2 Which is a unit for density - correct answer lbs/cm3 Which wave propagates in a medium - correct answer sound The range for ultrasound is - correct answer greater than 20KHz ____ is the number of wave cycles per second - correct answer frequency One kilohertz is equal to - correct answer 1,000 cycles per second One megahertz is equal to - correct answer 1,000,000 cycles per second The useful frequency range for clinical imaging ultrasound is - correct answer 2 MHz to 10 MHz Frequency is determined by the - correct answer source Frequency affects all of the following, except: wavelength, resolution, penetration, impedance - correct answer impedance The times per cycle is - correct answer period The period for a 5 MHz probe is - correct answer 0.2usec If frequency increases, period will - correct answer decreases Period is determined by the - correct answer source Period multiplied by the number of cycles in a pulse equals - correct answer pulse duration The distance between cyclical peaks is - correct answer wavelength The symbol for wavelength is - correct answer lambda The wavelength of a 5 MHz probe in soft tissue is - correct answer 0.3 mm As frequency increases, wavelength (assume same medium) - correct answer decreases Wavelength is determined by the - correct answer source and medium As wavelength decreases - correct answer resolution improves The rate at which a sound vibration propagates through a medium is called all of the following, except: sound speed, prop speed, speed of sound, velocity - correct answer velocity The units for propagation speed include all the following, except: km/sec, mph, msec, mm/sec - correct answer msec The average speed of sound in soft tissue is - correct answer 1540 m/sec Arrange the following in increasing order of sound speed in soft tissue - correct answer air, fat, muscle, soft tissue, muscle, bone The prop speed of sound of the ceramic lead zirconate titanate (PZT) is approx - correct answer 4000 m/sec speed of sound is determined by - correct answer medium The peak variation minus the mean variation is - correct answer amplitude All of the following are possible units for amplitude, except: degrees, decibels, Pascal, watts - correct answer degrees The maximum variation of an acoustic variable is 60. The mean value is 45. The maximum value is 30. The amplitude is - correct answer 15