Match the following criteria of material failure, under biaxial stresses $${\sigma _1}$$and $${\sigma _2}$$ and yield stress $${\sigma _y}$$ with their corresponding graphic representations:
$$P.$$ Maximum normal stress criterion
$$Q.$$ Maximum distortion energy criterion
$$R.$$ Maximum shear stress criterion

Which theory of failure will you use for aluminium components under steady loading is

A solid shaft can resist a bending moment of $$3.0$$ $$kNm$$ and a twisting moment of $$4.0$$ $$kNm$$ together, then the maximum torque that can be applied is

Two shafts $$A$$ and $$B$$ are made of the same material. The diameter of shaft $$B$$ is twice that of shaft $$A.$$ The ratio of power which can be transmitted by shaft $$A$$ to that of shaft $$B$$ is