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CHPTER 1 Calculate the pressure exerted by 5 kg of nitrogen gas at a temperature of 10ºc if the volume is 0.4cubic meter. Molecular weight of nitrogen is 28.Assume ideal gas laws are applicable. take universal gas constant (MR) = 8314 Nm/kg-mole-K At a depth of 9 km in the ocean, the pressure is 9.5*104 kN/m2. The specific weight of the ocean water at the surface is 10.2 kN/m3 and its average Bulk modulus is 2.4*106 kN/m2. Determine: - (i) The change in specific volume, (ii) The specific volume at 9 km depth and (iii) The specific weight at 9 km depth A disc of 100 mm diameter rotates on a table separated by an oil film of 2 mm thickness. Find the torque required to rotate the disc at 60 rpm, if the dynamic viscosity of oil is 0.05 poise. Assume the velocity gradient in oil film to be linear. A flat plate 30 cm x 50 cm slides on oil ( μ = 0.8 N-s/m2 ) over a large plane surface. What is the force required to drag the plate at 2m/s if separating oil film is 0.4 mm thick ? CHAPTER 2 A U-tube manometer is used to measure the pressure of water in a pipe line, which is in excess of atmospheric pressure. The right limb of the manometer contains mercury and is open to atmosphere. The contact between water and mercury is in the left limb. Determine the pressure of water in the main line, if the difference in level of mercury in the limbs of U-tube is 12cm and the free surface of mercury is in level with the centre of the pipe. If the pressure of water in pipe line is reduced to 9810 N/m2. Calculate the new difference in the level of mercury. A U – tube manometer ( Fig.1 ) measures the pressure difference between two points A and B in a liquid of density ρ1 . The U-tube contains mercury of density ρ2 . Calculate the difference of pressure between points A and B if the liquid contain at A is water and liquid contain at B is an oil of specific gravity 0.9. Take a= 1.5m, b = 0.75m and h= 0.50 m An example using the u-tube for pressure difference measuring In the figure below two pipes containing the same fluid of density U = 990 kg/m3 are connected using a u-tube manometer. What is the pressure between the two pipes if the manometer contains fluid of relative density 13.6?