The fundamental frequency of a wire stretched with a 2 kg wt is 100 Hz. The weigth required to produce its octave will be

Options

A. 4 kg wt
B. 8 kg wt
C. 12 kg wt
D. 16 kg wt

Answer

B

Explanation

Octave means the new frequency is 2n
`n propto sqrtT :. n_(2)/n_(1) = sqrt(T_(2)/T_(1))`
` :. T_(2) = T_(1) [n_(2)^(2)/n_(1)^(2)] = 4T_(1) = 8kg`. wt.