The fundamental frequency of a closed organ pipe is equal to the first overtone frequency of an open organ pipe. If length of the open pipe is 60 cm, the length of the closed pipe will be:
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The fundamental frequency of a closed organ pipe is equal to the first overtone frequency of an open organ pipe. If length of the open pipe is 60 cm, the length of the closed pipe will be:

G1 Physics · Accepted Answer

For the closed pipe fundamental: f₁ = v/(4L₁) For the open pipe first overtone: f₂ = v/L₂ Given f₁ = f₂: v/(4L₁) = v/L₂ L₂ = 4L₁ 60 = 4L₁ L₁ = 15 cm