Question

93.

A spherical particle falling at a
terminal speed in a liquid must have the gravitational force
balanced by the drag force and the buoyant force. The buoyant force
is equal to the weight of the displaced fluid, while the drag force
is assumed to be given by Stokes Law,
?s=6????.Fs=6πrηv.
Show that the terminal speed is given by
?=2?2?9?(?s−?1)v=2R2g9η(ρs−ρ1)*R*
is the radius of the sphere,
?sρs
is its density, and
?1ρ1
is the density of the fluid, and
?η

Answer #1

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