NEET-XI-Physics

exam-2 year:2016

with Solutions - page 3
  • #133
    The second overtone of an open organ pipe has the
    same frequency as the first overtone of a closed pipe
    L metre long. The length of the open pipe will be
    (1)``\frac {L}{2}``
    (2) 4 L
    (3) L
    (4) 2 L
    digAnsr:   4
    Ans : (4)
    Sol. For second overtone (3rd harmonic) in open organ
    pipe,
    0
    0
    3 2
    2 3

    = &implies;  =


    for first overtone (3rd harmonic) in closed organ pipe,
    C
    C
    3 4 4L
    4 3 3

    = &implies;  = =


    So, 0 0
    2 4L
    2L
    3 3
    = &implies; =