Question

An open organ pipe has fundamental frequency of 300Hz. If speed of sound in air is 330ms${}^{-1}$ the length of the pipe is

• A. 10cm
• B. 20cm
• C. 55cm
• D. 75cm

Answer 1

Answer: (C)

55cm

Open pipe has fundamental frequency, ${\nu }_o=\frac{\nu }{2L}=300Hz$

Speed of sound $\left(\nu \right)=330m/s$

$\Rightarrow \frac{\nu }{2L}=300$

$\Rightarrow \frac{330}{2L}=300$

$\Rightarrow L=\frac{330}{2\times 300}$$=0.55m$$=55cm$