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Sound waves

Sound waves

by Chandni Bhatia -
Number of replies: 2
In a Quincke's experiment ,the sound intensity has a minimum value I at a particular position.As the sliding tube is pulled out by a distance of 16.5 mm ,the intensioty increases to a maximum of 9I.Take the speed of sound,in air to be 330m/s.(a) Find the frequency of the sound source.
In reply to Chandni Bhatia

Re: Sound waves

by Manish Verma -

Path difference in the two cases = 2 x 16.5 mm

Path difference for constructive interference = \(n\lambda\)

Path difference for destructive interference = \(\(n+\frac{1}{2}\)\lambda\)

Since maxima is observed during sliding it may be assumed that it should be the nearest one.

Nearest gap between \(n\lambda\) and \(\(n+\frac{1}{2}\)\lambda\) is \(\frac{\lambda}{2}\)

\(\frac{\lambda}{2}=33 mm\)

Now, frequency can be found.