Question

A tube closed at one end and containing air produces fundamental note of frequency of $256Hz$. If the tube is open at both ends, the fundamental frequency will be

• A. $512Hz$
• B. $384Hz$
• C. $128Hz$
• D. $64Hz$

Answer 1

The correct option is A $512Hz$

For closed organ pipe, frequency of the fundamental note

${\nu }_{oc}=\frac{v}{4l}$, where v is velocity of sound and $l$ is the

length of the pipe.

For open organ pipe, frequency of the fundamental note

${\nu }_{oo}=\frac{v}{2l}=2{\nu }_{oc}=2\times 256=512\text{Hz}$