Question

In a closed organ pipe of length 105cm, standing waves are set up corresponding to the third overtone. What distance from the closed end, a pressure node is formed?

• A. 5 cm
• B. 45 cm
• C. 25 cm
• D. 30 cm

Answer 1

The correct option is B 45 cm

Given,

$\lambda =105cm=1.05m$

Third overtone of closed pipe.

$l=\frac{7\lambda }{4}$

So, $\frac{\lambda }{4}=\frac{l}{7}=\frac{1.05}{7}=0.15m$ or 5 cm

From closed end,

$3\times 15=45cm$