# us physics

 name 4 acoustic variables pressuredensitytemperatureparticle motion what is nyquist criteria f(max)=f sampling 2 what is propigation velocity in soft tissue 1540 m/s how many mu sec does it take sound to travel 1cm 6.5 mu sec how long does it take to image to a depth of 1cm 6.5 mu sec x 2cm (travel time)= 13mu sec what is density represented by? p what is density equasion density(p) = mass kgvolume m3 What are the 4 wave parameters frequency/period wavelenghtpropagation velocityamplitude what is frequency/ period determined by and what are its units wave source cycles/second or HZ what is wavelength determined by wave source and medium any form of distance mm what is propagation velocity determined by and what are its units medium m/s what is amplitued determined by and what is its units wave source but decreases with distancevolts or Decibels dB what is the equasion for wavelength wavelenght = propigation velocityfrequency lamda= c/f define amplitude size, strength, or volume what is amplitued equasion max- mean mean-min max-min 2 what is range of infrasound <20Hz What is range of Ultrasound >20 kHz What is range of audible sound 20Hz-20kHz What is formula for bulk modulus? stress strain change in pressurechange in volumevolume High bulk modulus material is incompressibleinelasticstiff low bulk modulus material is compressibleelasticnot stiff what is equasion for prop v as related to Bulk modulus c=square root of B modp (density) what is prop v in air 331 What is prop v in bone? 4080 m/s what is prop v in soft tissue? 1540 m/s what is prop v range for gases ie... air, helium, hydrogen 331-1286 m/s what is prop v range for liquids ie... water, alcohol 1130-1530 m/s what is prop v range for solids ie... lead, steel , diamonds 1322- 12,000 m/s higher bulk modulus does what to prop v increase lower bulk modulus does what to prop v decreases power is directly proportional to voltage2 or Amplitude2 What does the transmit power button control? changes the signals amplitude what are alternitive names for transmit power? acoustic poweroutput powertransmit gainpower gainoutput intensityacoustic output intensity is directly proportional to what? power what is intensity equasion? Intensity= power watts Beam area m2 OR amplitude2 beam area what is the power equasion for dB dB= 10 x log(PfPi) Pf is power finalpi is power initial what is the amplitude equasion for dB dB= 20*log (Af) Ai af is amplitude finalai is amplitude initial Authormelissausp ID70449 Card Setus physics Descriptionchapter 2 Updated2011-03-03T17:43:35Z Show Answers