The fundamental frequency of an air column in a pipe closed at one end is 100 Hz. If the same pipe is open at both the ends, the frequencies produced in Hz are

Options

A. `100, 200, 300, 400, ….`
B. `100, 300, 500, 700, ….`
C. `200, 300, 400, 500, ….`
D. `200, 400, 600, 800, ….`

Answer

D

Explanation

For a pipe closed at one end, the fundamental frequency
`n_(c) = v/(4L) = 100` Hz
For an open pipe, fundamental frequency `(n_(o))` is given by
`n_(o) = v/(2L) = 2 (v/(4L)) = 2 xx 100 ` Hz
and in an open pipe all multiples of `n_(o)` are produced i.e. the frequencies will be `200, 400, 600, 800`...