A differential element is subjected to the stresses (in kpsi): σ1 = 10, σ2 = 0, σ3 = –20. A brittle material has the strengths (in kpsi) Sut = 50, Suc = 90. Calculate the safety factor and draw σ1– σ3 diagrams of each theory showing the stress state using:(a) Coulomb-Mohr theory.(b) Modified-Mohr theory.

Estimate the change in specific internal energy au and specific enthalpy h from inlet to outlet for ethylene glycol (a liquid) flowing through each of the following devices: (a) a heat exchanger where the glycol temperature increases from 20 °c to 80 °c; (b) a pump operating at about 25 °c and increasing the glycol pressure from 100 kpa to 8 mpa.