The fundamental frequency of a closed organ pipe is same as the first overtone frequency of an open organ pipe. If the length of open pipe is 50 cm, the length of closed pipe is:
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The fundamental frequency of a closed organ pipe is same as the first overtone frequency of an open organ pipe. If the length of open pipe is 50 cm, the length of closed pipe is:

G1 Physics · Accepted Answer

Step 1: Closed-pipe fundamental frequency is v/(4L꜀), while the first overtone of an open pipe is v/Lₒ. Step 2: Equating them gives L꜀ = Lₒ/4 = 50/4 = 12.5 cm. Final: B.