A plate 0.06 mm distant from a fixed plate moves at 1.2 m/s and needs a force of 2 N/m 2 to maintain its speed. Calculate the viscosity of the fluid used between the plates. A circular disc of...

A plate 0.06 mm distant from a fixed plate moves at 1.2 m/s and needs a force of 2 N/m²
to maintain its speed. Calculate the viscosity of the fluid used between the plates.

A circular disc of diameter d is slowly rotates in a liquid of large viscosity m at a small distance h from a fixed surface. Derive an expression for torque T required to maintain an angular speed of ω.