ardms spi test.docx

What is the vertical axis of the graph called? - correct answer Y-axis What is the name of the horizontal axis of a graph? - correct answer X-axis What is the reciprocal of 1,000? - correct answer 0.001 What is the metric system order from highest to lowest? - correct answer Giga,mega,kilo,hector,deca,deci,centi,milli,micro,nano What are the prefixes in order? - correct answer M,k,da,d,Mega,kilo, deca,deci,centi What is the reciprocal of Mega? - correct answer Micro what is the term used to describe the effects of an ultrasound wave on living tissue? - correct answer Bioeffects as sound travels through a medium, what term describes the effects of the medium on the sound wave? - correct answer Acoustic propagation properties sound can be characterized as? - correct answer Cyclical oscillations in certain variables the direction of motion of a particle is perpendicular to the direction of propagation of the wave. What type of wave is this? - correct answer Transverse wave a particle within a transverse wave is traveling vertically. What is the direction of the waves propagation? - correct answer Horizontal what describes the characteristics of a sound wave? - correct answer Mechanical, longitudinal sound is best described as? - correct answer A series of compressions and refractions sound waves are ______ waves - correct answer longitudinal what are acoustics varibles? - correct answer Pressure, motion of particles in the wave, density what are the units of pressure measurement of an acoustic wave? - correct answer Atmospheres-atm, pascals-pa, millimeters of mercury-mmhg, pounds/sq in (all are appropriate but pa are most often used pressure is defined as an amount of ____ divided by the ___ - correct answer force,area period is described in units of ____ - correct answer time waves that exist at the same location and time will combine together. This is called? - correct answer Interference two waves arrive at the same location and interfere. The resultant sound wave is smaller. What is this called? - correct answer Destructive interference a pair of waves are in phase. What occurs when these waves interfere? - correct answer Constructive interference what is the reciprocal of period? - correct answer Frequency the range of periods commonly found in waves produced by ultrasound systems is? - correct answer 0.1-0.5 microseconds what happens to period as is propagates? - correct answer Remains the same the sonographer ____ have the ability to alter the period of an ultrasound wave by a basic transducer? - correct answer Does not what determines the period of an ultrasound wave? - correct answer The sound source what term describes the number of cycles that an acoustic variable completes in one second? - correct answer Frequency in imaging, the frequency of the wave remains ___ as it propagates through the body - correct answer constant what is the range of frequencies emitted by transducers used in ultrasonic imaging? - correct answer 2,000,000 to 10,000,000 Hz or 2-10 megahertz ultrasound is defined as a sound with a frequency of ___ - correct answer greater than 0.02 MHz or 20,000 Hz Which of the following waves is ultrasonic and least useful? - correct answer 24 kHz When a number is squared it is multiplied by? - correct answer Itself What diagnostic imaging the sonoghrapher ___ the ability the vary the amplitude - correct answer has The amplitude is changed by the _____ - correct answer output power The power of an ultrasound can be reported in? - correct answer watts If amplitude is increased, then so is ____ - correct answer power Changes in power of a wave are proportional to the waves amplitude squared. When ½ of the waves orginanal amplitude remains, only ___ of the original power remains - correct answer ¼ Intensity of an ultrasound beam is defined as? - correct answer Power divided by area As power increases, the ____ also increases - correct answer intensity The amplitude of an acoustic wave is increased. Which will most likely reaminn unchanged? - correct answer Frequency and period The wavelength is determined by the - correct answer source and medium ____ wavelength sound creates higher quality images with greater detail - correct answer shorter The relationship between frequency and wavelength are ___ - correct answer inverse As the wave travels through a faster medium the wavelength _____ - correct answer increases Which of the following lists in increasing order of propagation speeds? - correct answer Gas, liquid, solid Compressibility describes a characteristic of a medium. Which 2 terms describe the same property as compressibility? - correct answer Stiffness and elasticity