


FN = Normal force = F cos θ
AN = Area = A / cos θ
Tensile stress = Normal force / Area = F cos θ / (A / cos θ) = F cos2θ / A
Shearing stress = Tangential force / Area = F sin θ / A cos θ = F sin 2θ / 2A
The shearing stress is maximum if sin 2θ = 1 or 2θ = 900 or θ = 450
