Question

Consider a situation in which there is a Newtonian fluid between two long coaxial uniformly moving cylinders of radius R and 2R. A) Force per unit length required to keep the inner cylinder moving is​

Answer 1

Answer:

Solution: 2v. avt ZZ dk . 3 1 Here we take at a small (de) a element 91 dv. distance from centue . We also consider that in the thickness der Velocity changes by Now, as We know that, Viscous fonce (f) = – N A du {oo -ve sign der it is frictional in nature } let consider length 'l' of fluid is sliding Over each other. So Surface area of contact (A) = 2rat Now, -naarl du da because.