Atube made of an aluminum alloy with ultimate strength u = 476 mpa has a diameter of 120 mm and a thickness of 4 mm. the tube is subjected to a constant bending moment of 2 kn·m and an internal pressure that repeatedly cycles between zero and a maximum of 15 mpa. determine: (a) the cycles that can be applied before failure nf, if the material follows the fatigue relationship a =a nf m, where a = 839 mpa and m = –0.102.

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise