I need to answer this for homework. Choose a structure. Suggest ways to minimize compression, tension, shear, and torsion on that structure.

Coiled springs ought to be very strong and stiff. si3n4 is a strong, stiff material. would you select this material for a spring? explain.

Steam at a pressure of 100 kpa and a quality of 50% initially fills a rigid vessel having a volume of 0.5 m^3. the steam is then heated, causing the pressure in the vessel to rise to 150 kpa. determine: i. the mass of the steam in the vessel. ii. the temperature and quality of the steam after the heating process. ii the mass of the vapour, mg and liquid, m in the vessel after the heating process. if the steam in the vessel is now further heated, what would the pressure and temperature in the vessel be when all steam has turned into saturated vapour? b. sketch the processes in part (a) and part (b) on p-v and t-v diagrams, indicating clearly the temperatures, pressures and the paths. c. (0.59kg, 111.4°c, 73%, 0.4307kg, 0.1 593kg, 2.11 bar, 121.84°c)

In an engine working on the diesel cycle the ratios of the weights of air and fuel supplied is 50: 1. the temperature of air at the beginning of the compression is 60 °c and the compression ratio used is 14: 1. what is the ideal efficiency of the engine. calorific value of fuel used is 42000 kj/kg. assume c, = 1.004 kj/kg k and c 0.717 kj/kg k for air