In the above question the value of stress is:

Options

A. `(Wl)/(2xA)`
B. `(Wl)/(4xA)`
C. `(2Wl)/(lA)`
D. `(4xW)/(lA)`

Answer

A

Explanation

From the figure it is clean that `2Tcostheta=W`
`impliesT=(W)/(2costheta)`
Now `costheta=(x)/(sqrt(l^2+x^2))=l(x)/([1+(x^2)/(2l^2)])`
If `(x^2)/(2l^2)` is neglected being small, then `costheta=(x)/(l)`
`T=(W)/(2x)`
Stress`=(T)/(A)=(((Wl)/(2x)))/(A)(Wl)/((2x)/(A))=(Wl)/(2Ax)`
Correct choice is (a).