The components of stress at a point in a body are as follows:

(i)

450 N/mm² tensile, acting horizontally.

(ii)

150 N/mm² compressive, acting vertically.

(iii)

100 N/mm² shearing, such that the shear force on the right-hand side of a

small cuboid element surrounding the point acts downwards.

(a)

(b)

(c)

For the point, determine by calculation or by a Mohr's stress circle:

the principal stresses and the direction of the principal planes;

the maximum shearing stress and the direction of the planes on which this acts;

the normal and shearing stresses on a plane at 45° clockwise from the planes on

which the 450 N/mm² tensile stress acts.