MHT CET 2018 Physics Solved Paper

(c) In case of closed organ pipe, fundamental frequency
n

V

4L

=

332

4×83×10−2

or, n = 100 Hz
Hence frequency of overtones n1:n2:n3 :------- = 1 : 3 : 3 i.e., 100,300,500,700 and900 Hz
So number of possible natural oscillationsof air column whose frequencies lie below1000 are 5.