At what tension a wire of length 75 cm and linear density `8xx10^(-3) kg//m` , will be resonance with a frequency of 100 Hz.

Options

A. 45 N
B. 90 N
C. 180 N
D. 300 N

Answer

C

Explanation

`n = 1/(2L) sqrt(T/m) :. n^(2) = 1/(4L^(2)) T/m`
` :. T = 4L^(2) n^(2) m = 4 xx 3/4 xx 3/4 xx 8 xx 10^(-3) xx 10^(4)`
` = 180` N