Question

Calculate the value of stress on a wire of steel having radius of 2 mm, when 10 kN of force is applied on it.
A. `7.76 xx 10^(8) Nm^(-2)`
B. `7.96 xx 10^(8) Nm^(-2)`
C. `6.96 xx 10^(8) Nm^(-2)`
D. `5.56 xx 10^(8) Nm^(-2)`

Answer 1

Given, force `F = 10 kN = 1 xx 10^(4) N`
Radius, `r = 2 mm = 2 xx 10^(-3) m`
Area, `A = pi r^(2) = pi xx (2 xx 10^(-3))^(2)`
`= 12.56 xx 10^(-6) m^(2)`
Stress `= ("Force")/("Area") = (1 xx 10^(4) N)/(12.56 xx 10^(-6) m^(2))`
`= 0.0796 xx 10^(10)`
Stress `= 7.96 xx 10^(8) Nm^(-2)`