A steel bar and an aluminum bar are joined end to end and fixed between two rigid walls as...

A steel bar and an aluminum bar are joined end to end and fixed between two rigid walls as shown in Figure P1.26. The cross-sectional area of the steel bar is As and that of the aluminum bar is Aa. Initially, the two bars are stress free. Derive general expressions for the deflection of point A, the stress in the steel bar, and the stress in the aluminum bar for the following conditions:

a. A load P is applied at point A.

b. The left wall is displaced an amount δ to the right.

FIGURE P1.26 Bi-metallic rod.