Question

The first overtone frequency of a closed organ pipe P₁ is equal to the fundamental frequency of an open organ pipe P₂. If the length of pipe P₁ is 30 cm, what will be the length of P₂?

Answer 1

The first overtone frequency of the closed organ pipe ν =3V/4L₁ 

The fundamental frequency of an open organ pipe  ν =V/2L₂ 

Equating, 3V/4L₁ = V/2L₂ 

→L₂ = 2L₁/3            {Given L₁ = 30 cm} 

→L₂ = 2*30/3 cm =20 cm.