2. Questions Bank
  3. JEE Main & Advanced
  4. Physics
  5. Wave Mechanics

JEE Main & Advanced Physics Wave Mechanics Question Bank Self Evaluation Test - Waves

  • question_answer
    The fundamental frequency of an open organ pipe is 300 Hz. The first overtone of this pipe has same frequency as first overtone of a closed organ pipe. If speed of sound is 330 m/s, then the length of closed organ pipe is

    A)  41cm

    B)  37cm

    C) 31cm

    D) 80cm

    Correct Answer: A

    Solution :

    [a] For open pipe, \[n=\frac{v}{2\ell }\], where \[{{n}_{0}}\] is the fundamental frequency of open pipe. \[\therefore \,\,\,\ell =\frac{v}{2n}=\frac{330}{2\times 300}=\frac{11}{20}\] As freq. of 1 st overtone of open pipe = freq. of 1 st overtone of closed pipe \[\therefore \,\,2\frac{v}{2\ell }=3\frac{v}{4\ell '}\] \[\Rightarrow \ell '=\frac{3\ell }{4}=\frac{3}{4}\times \frac{11}{20}=41.25cm\]


You need to login to perform this action.
You will be redirected in 3 sec spinner