Given : Frequency of tuning fork, n=264Hz Length of column L=? For closed organ pipe n=
v
4l
⇒l=
v
4n
=
330
4×264
=0.3125 or, l=0.3125×100=31.25cm In case of closed organ pipe only odd harmonics are possible. Therefore value of l will be (2n−1)l Hence option (b) i.e. 3×31.25=93.75cm is correct.