Question

Principal stress what is value of theta when shear stress zero

Answer 1

$\mathfrak{The\:Answer\:is}$

At the principal stress angle, θp, the shear stress will always be zero, as shown in the diagram. And the maximum shear stress will occur when the two principal normal stresses, σ1 and σ2, are equal. In some situations, stresses (both normal and shear) are known in all three directions.

$\boxed{Hope\:This\:Helps}$