The head-discharge relationship for a certain pump can be represented by the equation H = 28-9Q2. The pump is fixed 2.5 m above the water surface in a river and it forces the water to a level 7.8 m above the pump. The suction and delivery pipes are 16 m and 764 m long, respectively and each pipe is 0.8 m in diameter. The pipe coefficient of friction is 0.005. The friction coefficient (Km) for the pump is 1.5. Estimate the time required to lift 1500 tons of water from the river by using this pump.

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Avolume of 2.65 m3 of air in a rigid, insulated container fitted with a paddle wheel is initially at 264 k, 5.6 bar. the air receives 432 kj by work from the paddle wheel. assuming the ideal gas model with cv = 0.71 kj/kg • k, determine for the air the amount of entropy produced, in kj/k

The catalogue for a refrigerant 22, four-cylinder, hermetic compressor operating at 29 r/s. a condensing temperature of 40°c and an evaporating temperature of -4°c shows a refrigeration capacity of 115 kw. at this operating point, the motor (its efficiency is 90 percent) draws 34.5 kw. the bore of the cylinders is 87 mm and the piston stroke is 70 mm. the performance data are based on 8°c of sub-cooling of the liquid leaving the condenser. compute (a) the actual volumetric efficiency and (b) the compression efficiency.