The coefficient of viscosity u can often be expressed with sufficient accuracy as a power of the absolute temperature of a gas, m T (2) = (2)" a) Recalling the relationship that exists between temperature and velocity in Couette flow, derive an expression for the wall shear stress Tu as a function of local velocity u and position y. Assume that m= 1 in the expression for above. b) For an adiabatic lower wall, what is the expression for T? Using the fact that is a constant in Couette flow, obtain an equation relating velocity u and position y in this adiabatic situation.