Question

The fundamental frequency of a closed organ pipe of length 20 cm is equal to the second overtone of an organ pipe open at both the ends. The length of organ pipe open at both the ends is(a) 100 cm(b) 120 cm(c) 140 cm(d) 80 cm

Answer 1

Correct option (a) 120 cm

Explanation :

For closed organ pipe, fundamental frequency is given by vc = v/4l

For open organ pipe, fundamental frequency is given by, v0 = v/2l'

2nd overtone of open organ pipe