Find the fundamental, first overtone and second overtone frequencies of an open organ pipe of length 20 cm. Speed of sound in air is 340ms−1.
If V=340 m/s,
I+20 cm ×10−2m
Fundamental frequency
=(V2I)=3402×20×10−2
=850 Hz
We known first over tone,
(2V2I)=2×3402×10×10−2 (for open pipe)
=1750 Hz
Second overtone
=3(V2I)=3×850=2500Hz