Sound pressure and intensity relate through air impedance of roughly 415 rayls
Evidence
Sound pressure is defined as force per unit area (pascals or N/m2), and can be measured via movement of the diaphragm of a microphone used in a sound level meter. In contrast, sound intensity is the power carried by the sound waves per unit area and has units of watts/m2. For the purposes of this course, intensity and pressure can be calculated from one another following this equation: where I is the intensity of sound, p is the pressure of the sound, and Z is the impedance of air. The impedance of air is a constant, and is roughly 415 rayls at 20° C. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 683
Categorization
Category: Definitional Content
- DEFINE: Technical definitions of sound pressure versus sound intensity and the air impedance constant that links them.
Related
- Sound pressure and intensity are distinct quantities interconvertible by a known relationship (similarity 0.88)
- Sound intensity measures power density as watts per unit area (similarity 0.84)
- Sound intensity measures energy transfer rate per unit area (similarity 0.83)
- Sound intensity is a vector describing the directional flow of sound energy. (similarity 0.83)
- Sound amplitude is measured as root mean square pressure because ears sense pressure (similarity 0.82)
- Sound level meters measure pressure, from which intensity is derived (similarity 0.81)
- Sound pressure is the small pressure deviation caused by a sound wave (similarity 0.81)
- Sound intensity level and sound pressure level are roughly equivalent (similarity 0.81)
- Air transmits sound efficiently because adjacent air cells are impedance matched (similarity 0.81)
- Sound pressure is tiny pressure deviation, and human hearing spans a specific Pa range (similarity 0.80)
- Sound pressure level and intensity level coincide only without reflecting surfaces (similarity 0.80)
- Pressure nodes in a sound field host maximal air flow which weakens sound intensity (similarity 0.79)
- All acoustic impedances are ratios of force to velocity (similarity 0.79)
- Sound intensity spans a trillion-fold range, forcing a logarithmic scale (similarity 0.78)
- Sound power level can be derived by dividing intensity by radiating area (similarity 0.78)