Concept in Definition ABC

In everyday life the term viscosity has a certain meaning, but it acquires a very different one if we refer to its scientific explanation. Thus, when touching certain sticky and dense substances, we say that they are viscous. This is what happens with honey, some dairy products, mustard, certain sauces, or some cosmetic products. From scientific criteria, viscosity is a law which was defined by Isaac Newton.

From a scientific point of view

Some fluid substances have a certain degree of internal friction and this phenomenon is known as viscosity. It is a force friction between adjacent fluid layers. In other words, viscosity is a endurance in the form of internal friction. In liquids, viscosity is mainly due to the electrical cohesion forces of the molecules that make up matter. In the gases, this phenomenon occurs due to collisions between molecules. From a scientific point of view, the study of viscosity must be placed in the area of ​​fluid mechanics.

Newton's Law of Viscosity

Viscosity is the friction between the different layers of a fluid. If a certain force is applied to each plate, this generates a stress on the fluid. Thus, a fluid is viscous when its mechanical energy it is not held constant and the fluid is non-viscous when held constant. This idea was explained by Newton through a law named after him. This law states that in a fluid the friction stress applied in one direction is proportional to its velocity and that said situation is measurable with a viscosity coefficient.

Fluid mechanics

A fluid is a substance that continuously deforms under the action of forces and can be a gas or a liquid. If we think of a pipe with a certain fluid inside, there are a number of aspects that determine the behavior of a fluid:

1) the pressure change,

2) the height at which the pipe is located (the deeper, the higher the pressure),

3) the area of ​​the pipe (the smaller the area, the lower the pressure) and

4) the flow velocity.

The viscosity of oil in engines

All liquids have a degree of viscosity and with respect to oils some have more viscosity than others. For a machine engine to function properly it is necessary that the oil used has a correct adhesion to the metal. Must think that oil protects the moving parts of an engine and, therefore, its viscosity has to adapt to changes in temperature that affect each engine.

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