A plane element in a body is subjected to a tensile stress of 100 MPa accompanied by a shear stress of 25 MPa.
Find
(i) the normal and shear stress on a plane inclined at an angle of 20° with the tensile stress
(ii) the maximum shear stress on the plane.

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.