Consider a L-long solid shaft AB with a varied diameter from D, at A to DR at B. Note that the diameter increases linearly with x (an axial coordinate of

the shaft measured from A as shown in the figure). The shaft is fixed on to a rigid wall at B and an external torque T, is applied at A.Take the shear modulus of the shaft as G and DR/DA = 3. Take the shear modulus of the shaft as G and DB/DA = 3. a) Find an algebraic expression for the maximum shear stress at the cross section that is x distance away from A. b) Find an expression for the angle of twist at A with respect to B (phiA/B).