Question

A certain steel has proportionallity limit of 3000 $kg/c{m}^2$ in simple tension. It is subjected to principal stresss of 1200 $kg/c{m}^2$ (tensile), 600 $kg/c{m}^2$ (tensile) and 300 $kg/c{m}^2$ (compressive). The factor of safety according to maximum shear stress theory is

• A. 1.50
• B. 1.75
• C. 1.80
• D. 2.00

Answer 1

The correct option is D 2.00

Proportionality limit shear stress
$=\frac{3000}{2}=1500kg/c{m}^2$
Maximum shear stress
$=\frac{1200-(-300)}{2}=750kg/c{m}^2$
Factor of safety
$=\frac{1500}{750}=2.0$