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

Options

A. `(3)/(4)`
B. `(4)/(3)`
C. `(1)/(2)`
D. 2

Answer

C

Explanation

`n_(0) = f_(1) = (v)/(2l ) `
`f_(2) = (v)/(4xx(1)/(4) l ) = (v)/(l) `
` therefore (f_(1))/(f_(2)) = ( (V)/(2l))/((V)/(l)) = (1)/(2) ` .
correct choice is (c).