Aconcentric cylinder viscometer may be formed by rotating the inner member of a pair of closely fitting cylinders (see fig). the annular gap is small so that a linear velocity profile will exist in the liquid sample. consider a viscometer with an inner cylinder of 4 in. diameter and 8 in. height, and a clearance gap width of 0.001 in., filled with castor oil at 90°f. determine the torque required to turn the inner cylinder at 400 rpm.

T = 52.76 ft . lbf

Explanation:

Given data:

inner diameter of cylinder 4 in

height of cylinder 8 in

gap width = 0.001 in

we know shear force is given as

Where, is torque acting on cylinder

is kinematic viscosity, for castor oil at 90 degree F  = 0.259 N s/m^2

substituing all value in   shear force formula we get

we know that

T = 52.76 ft . lbf

increasing transnational kinetic energy. because the transnational kinetic energy formula consists of only two variables, mass and velocity, increasing one of those properties is the only way to increase an object's transnational kinetic energy. increases to mass and velocity, however, do not have the same impact.