q4. (assessment criteria 3.1) state newton's law of cooling and define the terms in the equation. 1. 2. obtain the solution when the initial liquid temperature is 100 c, the ambient temperature is 2 and the thermal time constant is 60 min. 3. plot the solution. remember to label the axis. 4. calculate the fluid temperature after one time constant.

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)