$4.$

Using the MOHR's Circle, determine

a$)$ the principal planes and stresses,

b$)$ the maximum shear planes and stresses,

c$)$ the stresses on an element oriented $\backslash (60^\{\backslash$circ$\}\backslash )$ counterclockwise from the element shown.

Where:

X is $2$

Y is $5$

YX is $52$

XY is $25$