To determine the sound propagation velocity in air by acoustic resonance technical one can use a pipe with a piston and a sonic membrane closing one of its ends. Find the velocity of sound if the distance between the adjacent positions of the piston at which resonance is observed at a frequency `v=2000Hz` is equal to `l=8.5 cm.`

Explanation

When the two positions of the resonance are obtained at distances `l_(1)` and `l_(2)` respectively, then the velocity v of sound is given by
`v = 2n (l_(2) - l_(1))`
Where nis the frequeny at resonance.
n = 2000 Hz,
`(l_(2) - l_(1))` = 8.5 cm = `8.5 xx 10^(-2)`
`v = 2xx2000xx8.5 xx10^(-2)`
-340m/s