Final answer:
The viscosity of motor oil can be calculated using the formula derived from Stokes' Law, which determines the drag force on a sphere moving through a fluid. We need to substitute the SI units for the radius of the sphere, its density, the density of the oil, and the terminal velocity of the sphere into the formula to find the viscosity. Without further data or formulas regarding the boundary layer thickness, we cannot calculate it.
Step-by-step explanation:
To calculate the viscosity of motor oil, we can use the observed terminal velocity of a sphere falling through the oil and apply the equation derived from Stokes' Law. For a steel ball of radius 0.8 mm falling with a terminal speed of 4.32 cm/s in motor oil with the given densities of the ball (7.86 g/mL) and the oil (0.88 g/mL), the viscosity (η) can be calculated using the formula: η = 2(g)(r^2)(ρs-ρl)/(9v), where g is the acceleration due to gravity, r is the radius of the sphere, ρs is the density of the sphere, ρl is the density of the liquid, and v is the terminal velocity.
We must convert all the units to consistent SI units before substituting them into the formula. The radius will be 0.8 x 10^-3 meters, the terminal speed will be 4.32 x 10^-2 meters per second, the densities will be 7860 kg/m^3 for the steel ball and 880 kg/m^3 for the oil. Once the values are substituted, we can solve for the viscosity.
The question regarding the boundary layer thickness (h) was probably involving a different formula or given set of data that is not provided here, so we cannot calculate it without that specific information. It is crucial to always verify the data provided before performing any calculations.