A closed organ pipe has length `L`. The air in it is vibrating in third overtone with maximum amplitude a . The amplitude at distance`(L)/(7)` from closed of the pipe is

Options

A. `a`
B. `a/2`
C. `(sqrt3)/(2)a`
D. `(1)/(sqrt2)a`

Answer

A

Explanation

The figure shows variation of displacement of particles in a closed organ pipe for `3^(rd)` overtone.
For third overtone `l=(7lamda)/(4)` or `lamda=(4l)/(7)` or `(lamda)/(4)=(l)/(7)`
Hence the amplitude at P at a distance `(l)/(7)` from closed end is `a` because there is an antinode at that point.