A pipe opened at both ends prpduces a note of
frequency `f_(1)`. When the pipe is kept with `3/4th` of its
length in water, it produces a note of frequency `f_(2)`.
The ratio `f_(1)/f_(2)` is

Options

A. `1 : 1`
B. ` 1 : 2`
C. ` 2 : 1`
D. ` 3 : 2`

Answer

C

Explanation

For an open pipe ,`f_(1) = V/(2L) `
In the second case, it is a pipe closed at one end
`f_(2) = V/(4(L//4)) = V/L :. f_(2)/f_(1) = 2/1 `