Question

The figure shows the state of stress at a certain point in a stressed body. The magnitudes of normal stresses in the x and y directions are 100 MPa and 20 MPa respectively. The radius of Mohr's stress circle representing this state of stress is

• A. 120 MPa
• B. 80 MPa
• C. 60 MPa
• D. 40 MPa

Answer 1

The correct option is C 60 MPa

Radius $=\sqrt{{\left(\frac{{\sigma }_x-{\sigma }_y}{2}\right)}^2+{\tau }_{xy}}$
GIven, ${\sigma }_x$ = 100 MPa, ${\sigma }_y$ = - 20 MPa
${\tau }_{xy}=0$
$\therefore Radius=\sqrt{{\left(\frac{100+20}{2}\right)}^2+0}$
= 60 MPa