Question

In an organ pipe of length L open at both ends, the fundamental mode has a frequency (where v is a speed of sound in air)

• A. $\frac{v}{2L}$ and only odd harmonics are present.
• B. $\frac{v}{2L}$and only even harmonics are present
• C. $\frac{v}{2L}$and all harmonics are present
• D. $\frac{v}{4L}$and only odd harmonics are present.

Answer 1

Answer: (C)

$\frac{v}{2L}$and all harmonics are present

Answer 2

An organ pipe of length L open at both ends vibrates with frequencies given by

$\upsilon_{n} = \frac{nv}{2L}$where n = 1,2,3,4,………

The fundamental frequency corresponds to n = 1 and is given by

$\upsilon_{1} = \frac{v}{2L}$

In an open pipe all harmonics are present