Afilm of paint 3 mm thick is applied to a surface inclined above the horizontal at an angle \theta. the paint has rheological properties of a bingham plastic with yield stress 15 pa and \mu[infinity]= 60 cp. with a specific gravity of 1.3, at what angle \ theta will the paint start to flow down the surface?

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.