What is viscosity and its unit?
definitions. Informally, viscosity is the quantity that describes a fluid’s resistance to flow. Fluids resist the relative motion of immersed objects through them as well as to the motion of layers with differing velocities within them. The SI unit of viscosity is the pascal second [Pa s], which has no special name.
Is poiseuille SI unit of viscosity?
The poiseuille (symbol Pl) has been proposed as a derived SI unit of dynamic viscosity, named after the French physicist Jean Léonard Marie Poiseuille (1797–1869). The equivalent cgs unit, the poise, symbol P, is most widely used when reporting viscosity measurements.
What is viscosity of water?
The viscosity of water is 1.0016 millipascals⋅second at 20 °C. That is for its dynamic viscosity.
What is poise pressure?
If you have poise, you are cool under stress. People with poise can handle pressure without showing it. If you’re calm while singing the national anthem in front of thirty million people, you’ve got a lot of poise. This is a rare quality people admire.
What is viscosity MPA s?
mPas at 20°C It is defined as the internal frictional resistance of a liquid to the application of a pressure or a shearing stress. The dynamic viscosity η (Greek letter eta) is normally given in millipascal-seconds (mPas) and is usually determined by using a rotary viscometer.
What is the SI unit of viscosity Mcq?
poiseiulle
Does viscosity increases as molecular weight increases?
A High molecular weight increases the impact resistance of the material. A High molecular weight increases the viscosity of the material – makes it harder to process the material using conventional methods. The longer the chains, the harder it is to get them to flow because they are more tangled.
What increases viscosity?
Viscosity generally increases as the temperature decreases. The viscosity of a liquid is related to the ease with which the molecules can move with respect to one another. Thus the viscosity of a liquid depends on the: strength of attractive forces between molecules, which depend on their composition, size, and shape.
What is the relationship between viscosity and molecular weight?
The larger the polymer, the more drag and also the more intermolecular attraction, and so the higher the viscosity. So, the viscosity increases with the molecular weight, but not necessarily in a linear way.
What is viscosity average molecular weight?
It is a measure for the broadness of a molecular weight distribution of a polymer, that is, the larger the polydispersity index, the broader the molecular weight distribution. The average molecular weight is related to the viscosity of the polymer under specific conditions.
Why do polymers have high viscosity?
The molecular weight of polymer is related to its molecular size, which means that polymers with a larger molecular size have a higher molecular weight. Polymers with a higher molecular weight provide higher viscosity, as shown in Figure p28.
Which is more viscous petrol or honey?
Water, gasoline, and other liquids that flow freely have a low viscosity. Honey, syrup, motor oil, and other liquids that do not flow freely, like those shown in Figure 1, have higher viscosities. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules.
Which has higher viscosity water or honey?
Viscosity is the measure of resistance of a fluid to flow. A fluid that is highly viscous has a high resistance (like having more friction) and flows slower than a low-viscosity fluid. Honey would move slower than water, so honey would have a greater viscosity.
Which is more viscous honey or ketchup?
Very viscous liquids tend to be long chained molecules. For example, honey has a much higher viscosity than water….What is Viscosity.
| Approximate Viscosities of Common Materials (At Room Temperature-70°F) * | |
|---|---|
| Material | Viscosity in Centipoise |
| Honey | 10,000 cps |
| Ketchup | 50,000 cps |
| Sour Cream | 100,000 cps |
What is the most viscous?
glycerol