Question

State Stoke’s law? What are the factors on which viscous drag depends?

Answer 1

Stoke’s law states the backward dragging force (F) acting on a small spherical body of radius r, moving through a medium having coefficient of viscosity η and velocity v is given by

F = 6πηrv

viscous drag (F) depends on 

1. coefficient of viscosity of the medium η

2. velocity of the body (v) 

3. radius of the spherical body (r)