springs

A closely coiled helical compression spring of mean coil diameter D and wire diameter d, is loaded by an axial force F. The maximum shear stress developed in the wire is

The process of shot peening increases the fatigue life of steel springs mainly because it results in

The figure shows arrangements of springs. They have stiff nesses $${{K_1}}$$ and $${{K_2}}$$ as marked. Which of the following arrangements offers a stiffness $$ = \,{{2{K_1}{K_2}}...