The air supply to an engine is measured by being taken directly from the atmosphere into a large reservoir through a sharp edged orifice of 50 mm diameter. The pressure difference across the orifice is measured by means of an alcohol manometer set at a slope of sin-1 (0.1) to the horizontal. Find the flow rate of air if the manometer reading is 271 mm, the relative density of alcohol is 0.8, Cd for the orifice is 0.602 and the atmospheric temperature and pressure are 15.8 degree C and 775 mm of mercury respectively. The relative density of mercury is 13.56 and R = 287 J/kg K for air.