An impedance tube, mounted in a room at 20oC, is used to evaluate experimentally the sound...

An impedance tube, mounted in a room at 20^oC, is used to evaluate experimentally the sound absorbing properties of some acoustic material. The maximum and minimum sound pressure levels at 500 Hz measured in the tube are 92 dB and 78 dB respectively. The first pressure minimum is found to occur at a distance of 0.1m from the face of the sound absorbing material.

Calculate

1) The ratio of the maximum to minimum pressure amplitude, SWR

2) The reflection coefficient, R for the sound absorbing material

3) The (normal incidence) absorption coefficient, α at this frequency

4) At what distance from the sample would the next minimum amplitude in sound pressure level occur?

5) What is the sound pressure level of the incident sound wave?

6) What is the sound power level of the incident sound wave?

Expert Solution

genius_generous answered 2 years ago

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