Basic Physics Flashcards
(17 cards)
SOUND WAVES are those pressure changes that human ear can
detect.
* They oscillate at frequencies of ____
* In order to be transmitted, sound requires a
medium containing molecules, and therefore
cannot travel through a vacuum
20-20,000 cycle per sec or Hz
ULTRASOUND
-defined as mechanical waves with
higher frequency than humans can
hear : mechanical waves with frequencies
> 20,000Hz, or 20kHz
Lower frequency sound less than 20Hz
Infrasound
2 types of Utz Waves
Transverse and longitudinal
Range of diagnostic UTZ
1-10 Mhz
Range of therapeutic UTZ
0.7-1.0 Mhz
Surgery UTZ
1-5 Mhz
Industrial
25-400 khz
Military
20-50khz
5 ACOUSTIC
VARIABLES/PROPERTIES OF
SOUND WAVE
- Wavelength
- Amplitude
- Period
- Frequency
- Velocity
– is the extent of one complete
Wavelength
. It is the change in magnitude of
a physical entity
Amplitude
Is the elapsed time between compression zones
or rarefaction zones
Period
Number of cycle per second
Frequency
Sound Propagation Media: EDCB
Elasticity, Density, Compressibility, Bulk Modulus
- it refers to the ability of an object to
return to its original shape and volume after a
force is no longer working on it.
As an utz wave travelling through soft tissue
causes elastic deformations by the separation
and compression of neighboring molecules
Elasticity
the basis of density alone we
would expect sound ( utz) to have a
greater velocity in __ (low density) than
in __ (high density)
Air, bone
