Final answer:
The Brookfield viscometer is typically used to measure the viscosity of PVP due to its ability to handle non-Newtonian fluids and its wide use in quality control applications.
Step-by-step explanation:
To measure the viscosity of polyvinylpyrrolidone (PVP), the appropriate type of viscometer is typically chosen based on the properties of the PVP solution in question. A common choice is the Brookfield viscometer, which is widely used for measuring the viscosity of liquids of varying viscosities, particularly in quality control applications. This type of viscometer utilizes a spindle rotated at a known speed within the sample, and the resistance to rotation is measured to calculate the viscosity. The Brookfield viscometer is especially useful for non-Newtonian fluids like PVP, which can display a change in viscosity under different shear rates.
Other types of viscometers mentioned, such as capillary and falling sphere viscometers, are better suited for other applications. Capillary viscometers are typically used for Newtonian fluids, and while falling sphere viscometers, also known as Stokes' law viscometers, are used to measure viscosity by observing the terminal velocity of a sphere through a fluid, they are not as commonly used for PVP as the Brookfield viscometer.