PROBLEM 6 (18 pts) Consider an elliptic crack shown below. You must show your work to receive full credit! (a) (6pts) Estimate the magnitude of the maximum stress that exists at the tip of this crack if the applied tensile stress is
100MPa
according to Inglis' theory. (b) (6pts) The plate shown above is subject to a tensile stress of
100MPa
. If the specific surface energy and modulus of elasticity for this glass are
0.5(J)/(m^(2))
and
80GPa
, respectively, will the crack continue to propagate? Judge using Griffith's theory accurately. (c) (6pts) The plate structure shown above is constructed from a steel alloy that has a plane strain fracture toughness
K_(Ic)
of
100MPa\sqrt(m)
. Estimate the maximum tensile stress that can be applied without having the crack to be propagated. Assume a value of 2.0 for
Y
.