I am always asked about viscousity, it has always been an abstract idea for many, in spite of the lengthy explanations most articles written about it. You may use our link "All about oils" for the schooled reference. This is also known as the box.
Now let's go out of the box.
Let's try asking the right questions:
In order to know more about viscousity, it is best to ask what is "The most viscous" material on earth.
Let's try this question asked by Mr. LOL:
"What is the thickest, most viscous substance known?
At ordinary temperature and pressure. Is it mercury?"
Yahoo answers gave us the following answers:
Best aswer:
"It would indeed be glass. it is defined as a "supercooled liquid". You can take really old glass and measure the thickness at the top and bottom and there is a definite difference.
Beyond that, I would guess VTB. The gummy tarry stuff that ends up at the (B)ottom of (V)acuum (T)owers in refineries. It is what is left when almost every other useful lighter end is removed. It is mixed with Mineral spirits or kerosene and reheated to make asphalt and the stuff in fluorescentt light ballasts for fire prevention."
Second best:
"Mercury is terrifically dense, but it isn't viscous. It flows very readily (so much that one of its older names is 'quicksilver') and pours like water.
Highly viscous fluids are things like tar and molasses, that pour really slowly. Some places will tell you that glass is a highly viscous liquid, which I think is BS but it gets repeated often and it might very well be the answer your teacher wants.
Edit: Old glass windows are thicker at the bottom because they were produced in nonuniform thicknesses via a pour or a crown glass process. When they were installed, it was easier to install them with the thick edge down.
Some old glass windows, installed by people who weren't paying attention, are found to be thinner at the bottom.
Wikipedia's article on glass, about a third of the way down, talks about the 'glass flowing' idea and is mostly dismissive. Its atoms aren't arranged in crystals but you'd have to watch glass for much longer than the age of the universe to observe any fluid behavior."
Third best:
"Glass.
Glass is not a true solid, or a crystal. It is closer
to liquid in structure.
Glass flows very very slowly. But its possible to
see the effects in windows that are hundreds of
years old, in which the bottom of the window is thicker than the top."
Viscousity defined: (source Wikipedia)
"Viscosity is a measure of the resistance of a fluid which is being deformed by eithershear stress or tensile stress. In everyday terms (and for fluids only), viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, whilehoney is "thick", having a higher viscosity. Put simply, the less viscous the fluid is, the greater its ease of movement (fluidity).[1]
Viscosity describes a fluid's internal resistance to flow and may be thought of as a measure of fluid friction. For example, high-viscosity felsic magma will create a tall, steep stratovolcano, because it cannot flow far before it cools, while low-viscositymafic lava will create a wide, shallow-sloped shield volcano.
With the exception of superfluids, all real fluids have some resistance to stress and therefore are viscous. A fluid which has no resistance to shear stress is known as an ideal fluid or inviscid fluid. In common usage, a liquid with the viscosity less than water is known as a mobile liquid, while a substance with a viscosity substantially greater than water is simply called a viscous liquid."
The GTO Advantage:
Please read our link on ALL ABOUT OILS for the explanation.
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