Question

A closed pipe and an open pipe have their first overtones identical in

frequency. Their lengths are in the ratio

[Roorkee 1999]

• A. 1 : 2
• B. 2 : 3
• C. 3 : 4
• D. 4 : 5

Answer 1

The correct option is C

3 : 4

If is given that

First over tone of closed pipe = First over tone

of open pipe $\Rightarrow 3\left(\frac{v}{4l_1}\right)=2\left(\frac{v}{2l_2}\right)):where{l}_{1}and{l}_2$ are the lengths of closed and open organ pipes

hence $\frac{l_1}{l_2}=\frac{3}{4}$