1.A .03 m3 rigid tank initially contains R134a at 1.4MPa and 100% quality. the tank is connected by a valve to a supply line that carries R134a at 36 C and 1.6MPa. determine the mass of R134a that had entered
2.Find the center of gravity of the given composite body when the specific weight of brass is .306 lb/in^3 and the specific weight of aluminum is .101 lb/in^3
3.An Element of soil (sand) behind a retaining wall is subjected to an increase in vertical stress of 60kPa and an increase in lateral stress of 25 kPa. Determine the increase in vertical and lateral strains, assuming the soil is a linearly elastic material with E=20MPa and v=.3
4.The tube supports the four parallel forces. Determine the magnitude of the forces and acting at C and D so that the equivalent resultant force of the four forces acts at point O.