When a force or stress is applied to a fluid, it flows, resulting in internal friction that resists the flow. Therefore, viscosity is defined as the internal friction of a fluid, or in other words, ...
Figure 2: Diagram of an Ostwald viscometer (A), a flow cup (B) and tube viscometer (C).Credit: Technology Networks. Pressurized versions of the capillary and flow cup viscometers can be used in order ...