Air is flowing in an insulated duct at a rate of 2 kg/sec. Air enters the duct at 40 oC and 8-kW of heat is added with a electric resistance heater. Find the exit temperature of air. (Cp=1.005 kJ/kgK) a) 44 b)30 c) 54 d) 60

Amixture of slurry and mud is to be pumped through a horizontal pipe of diameter 500 mm. the fluid behaves as a bingham plastic with a yield stress of 30 pa and viscosity 0.04 pa.s. describe the effects of the shear stress through a transverse section of the pipe by plotting the variation in shear stress and velocity profile: (i) just before the slurry starts to move (ii) as the slurry flows when the pressure gradient is double that in part (i)