Viscosity is the viscosity or viscosity of a liquid or gas. A model is used that consists of two superimposed plates. Between these plates is a substance that adheres to both plates. In our imagination, the substance is divided into parallel layers. One plate is now pulled in one direction, with forces now acting on the layers of the fabric, while the other plate rests. The first adjacent layer is pulled along with the moving plate, whereas the layer on the stationary plate is stationary.<\/p>\n
Each layer passes on the speed of movement to the next layer differently. The speed naturally decreases from the moving plate to the stationary plate. This is because the particles of the material are in each other's way, so to speak, and have to \u201epass\u201c each other. Electrostatic forces of attraction also act between the smallest particles. How quickly or slowly the layers move therefore depends on the properties of the substance and determines the viscosity. Substances are divided into low, medium and high viscosity. You can now imagine that a substance with a high viscosity is less flowable than a substance with a low viscosity.<\/p>\n
In practice, the unit of measurement Pascal second (Pas) has become established. There is also the unit millipascal second (mPas) for substances with low viscosity. mPas is now more common.<\/p>\n
The centistokes (cST) unit is also used (see below under outlet beakers).<\/p>\n
The viscosity of a substance is also influenced by other factors. For example, and most influential, is the temperature. Viscosity decreases with increasing temperature. As the temperature falls, it rises again. It is therefore important to specify the temperature when determining the viscosity.<\/p>\n
Of course, viscosity also depends on other factors, such as specific material properties like the shape and size of the molecules, etc.<\/p>\n
To give you a better idea of the abstract, here are some examples from everyday life. Of course, these are only approximate values, as the viscosity of some substances can vary from type to type, for example honey:<\/p>\n
| Fabric<\/td>\n | Temperature<\/td>\n | Viscosity approx. in mPas<\/td>\n<\/tr>\n |
| Water<\/td>\n | 20\u00b0C<\/td>\n | 1,009<\/td>\n<\/tr>\n |
| Olive oil<\/td>\n | 20\u00b0C<\/td>\n | 100<\/td>\n<\/tr>\n |
| Mayonnaise<\/td>\n | 20\u00b0C<\/td>\n | 2.000<\/td>\n<\/tr>\n |
| Honey<\/td>\n | 20\u00b0C<\/td>\n | 10.000<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n |