Viscosity is the thickness of a liquid, cause by the friction between the molecules in that liquid. A very high viscosity would result in a solid form and low would be a liquid. If a liquid as zero viscosity is only found in superfluids at there freezing points or lower. There are also two types of viscosity “dynamic” (which is measure in seconds, pascal seconds to be exact) and “kinematic” (which is measured in metre per second squared)
Fun fact they use viscosity to predict when volcanoes are going to erupt:)
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