1.

Find the temperature at which the fundamental frequency of an organ pipe is independent of small variation in temperature in terms of the coefficient of linear expansion ( alpha) of the material of the tube.

Answer»

`1//3alpha`
`1//2ALPHA`
`1//4alpha`
`1//5alpha`

Solution :Fundamental frequency of an organ pipe,
`f=(v)/(2l)` where `l` is length of the organ pipe at temperature `T`
Also, `l=l_(0)[1+alpha(T-T_(0))]`
VELOCITY of sound, `v=sqrt((gammaRT)/(M))`
We have to find the temperatureat which
`f(T')=f(T_(0))` for small `(T-T_(0))`
`(sqrt((gammaRT)/(M)))/(2l_(0)[1+ alpha(T-T_(0))])=(sqrt ((gammaRT_(0))/(M)))/(2l_(0))rArrsqrt((T)/( T_(0)))=1+alpha(T-T_(0))`
`" "[1+((T-T_(0))/(T_(0)))]^(1//2) =1+alpha(T -T_(0))`
For small ` (T-T_(0))` we may use binomial APPROXIMATION,
`1+(1)/(2)((T-T_(0))/(T_(0 )))= 1+alpha(T-T_(0))`
`(1)/(2)((T-T_(0))/(T _(0)))=alpha( T-T_(0)),alpha=(1)/(2T _(0))orT_(0)=(1)/(2alpha)`


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