1. Describe the condition of plain stress and plain strain conditions in terms of stress and strains (01, 02, 03, 01, 81, 82, 83).

[2 5 71 The Green strain tensor (E) is 5 2 2 MPa. [725] Determine the three principal invariants (J₁, J2, J3) of E, the value of the maximum normal strain (En max) and its unit direction, the maximum shear strain (Es max) and its unit direction.

Problem 1. A material element in plane stress is subjected to stresses: Ox = -7000 psi Oy = -3000 psi = -4000 psi Txy а) Find the stresses ox,, Oy,, and Tx, y, on an element oriented at an angle 0 = 30° clockwise from the x axis and show these stresses and on a sketch of a properly oriented element. b) Find the principal stress angles, Op1, Op2, and the principal stresses, 01,02 c) Find the maximum shear stress angles, 051, es2, and the maximum shear stresses, +Tmax- d) Show the principal stresses and maximum shear stresses on a sketch of a properly oriented element

5) Determine the absolute maximum shear stress for the stress shown. 5) Determine the absolute maximum shear stress for the stress shown.Problem 3 What is the absolute maximum shear stress for the stress element shown on the right? Problem 3 What is the absolute maximum shear stress for the stress element shown on the right? 90 ks 30 ks 40 ksi