The velocity of transverse wave in a wire of density `8000 kg/m^(3)` is 300 m/s. The tensile stress in the wire is

Options

A. `3 .6 xx 10^(8)N/m^(2) `
B. `7.2 xx 10^(8) N//m^(2) `
C. `5 xx 10^(8) N//m^(2) `
D. `2 xx 10^(9) N//m^(2) `

Answer

B

Explanation

`V = sqrt(T/m) :. V^(2) = T/m = T/(pi r^(2) xx 1 xx d) `
` :. " Stress " = T/(pi r^(2)) = V^(2) d `
` :. " Stress " = 300 xx 300 xx 8000 = 7.2 xx 10^(8) N//m^(2) `