6. The following data have been obtained regarding the viscosity of a maple syrup ; Shear rate (s-1 ) Shear Stress (Pa ) 820 74.0 30 - 22.6 Calculate the viscosity of the fluid at each shear rate , and identify the type of fluid that the syrup is 7. Calculated the predicted viscosities of (a) liquid methane at -165 .C and atmospheric pressure ; and (b ) methane gas at 25 .C and atmospheric pressure (give your answers in Pas ). For interest - compare your calculated value with data available in handbooks so that you get a feel for the relative accuracy of these theoretical approaches 8. Pure oxygen has a viscosity of 207.2 x 10- Pas at 25 .C and 1 atmosphere Pure Nitrogen has a viscosity of 178.2 x 10- Pas under those conditions Estimate the viscosity of air (in Pas ) if it is assumed that the mole fraction of oxygen in air is 0.21 , and Oxygen and Nitrogen are the only significant components of air 9. (a) A Couette viscometer has inner cylinder 5 cm in diameter and an outer cylinder 5.2 cm in diameter . The length of the bob section (sustaining the Torque ) is 10.0 cm. The viscometer is being used to determine the viscosity of an incompressible Newtonian liquid that has a density of 1100 kg /m. The measured torque is 0.02 Newton metres , and the angular velocity of the viscometer is 60 rpm . Determine the viscosity of the liquid (b) The Couette Viscometer is accurate if the Reynolds number remains sufficiently low that Taylor vortices do not arise in the viscometer . Determine whether the result of part (a ) should be regarded as accurate