When small aerosol particles or microorganisms move through air or water, the

Reynolds number is very small $($Re $1).$ Such flows are called creeping flows. The

aerodynamic drag on an object in creeping flow is a function only of its speed V$,$ some

characteristic length scale L of the object, and fluid viscosity $($Fig$.$ P$758).$ Use

dimensional analysis to generate a relationship for FD as a function of the independent

variables.