If a low carbon steel A-36 must withstand 240 MPa of tensile stress, what is the maximum allowable length on an internal elliptical flaw whose radius of curvature at the flaw tip is 3 micrometer? Assume that the major axis of the elliptical flaw is perpendicular to the tensile loading axis and that the theoretical strength of a material is a tenth of its Youngs modulus.

Acantilever of 3 m length with a t-shaped cross-section is loaded by three concentrated loads: w,-80 n at the free end, w 30 n, and w,-60 n at a distance of 1 m from the free end. all loads are applied at the outer edges of the flange as indicated in the sketch below. (a)-determine the maximum torsional shear stresses in the flange and in the web at distances 0.5 m and 2.5 m from the free end (sections i and ii marked in the sketch) b)- determine thefh end cross section assuming a shear modulus of 210 gpa.