Answer to Question #237120 in Physics for lyn

Question

A plate moves at 2 m/s with a shearing force of 3.5 N/m2. The distance between moving plate and fixed plate is 0.08mm. Determine viscosity of fluid between plates.

Answer 1

The ratio of the shearing force to the area is

$$\tau=\frac FA.$$

On the other hand, it is

$$\tau=\mu\frac{u}{t}.\\\space\\ \tau=\mu\frac{u}{t},\\\space\\ \mu=\frac{\tau t}{u}=\frac{(3.5)(0.08·10^{-3})}{2}=1.4·10^{-4}\text{ Ns/m}^2.$$