For the organ pipe closed at one end, the fundamental frequency of the wave of wavelength λ is given by, n_{0} = v/4L. The frequency of i^{th} over tone is given by n_{1} = (i + 1) x n_{0} where i = 1,2,3 ...etc. frequency of the fundamental

(a) n_{0} = v/4L where n_{0} = frequency of the

fundamental = n_{0} = 330/4 x 0.15 = 550Hz

(b) The first four overtones are 2n_{0} , 3n_{0} , 4n_{0} ,and 5 n_{0}. So, the required frequencies are 1100, 2200, 3300, 4400, and 5500 Hz.

(c) the frequency of the nth overtone is (2n + 1)r

(2n + 1)n_{0} = 20000; or (2n + 1) 550 = 20000

or n = 17.68

Or n = 17.18 the acceptable value is 17.