An oil storage tank has one side sloping at 60° to the horizontal. a circular opening of diameter 300mm is cut into the side of the tank, and is covered by a plate bolted into place. the level of oil in the tank is 1.2m above the top of the opening. find: (a) the force acting on the plate (b) the depth of the centre if pressure for the plate below the surface of the oil

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.