What is a key characteristic of fluids with low viscosity?

Fluids with low viscosity are characterized by their ability to flow easily. Viscosity refers to the internal resistance of a fluid to flow; thus, a fluid that has a low viscosity encounter less resistance, allowing it to move more freely. For example, water is a low-viscosity fluid compared to syrup, which flows much slower because of its higher viscosity. This property makes low-viscosity fluids ideal for applications where quick movement is necessary, such as in hydraulics or lubrication systems.

In contrast, fluids with high viscosity tend to flow more slowly and resist movement, resulting in a thicker consistency that can impede their flow. The density of a fluid does not inherently determine its viscosity; low-viscosity liquids can be either dense or light, depending on their composition. Thus, the ability of low-viscosity fluids to flow more easily is a defining characteristic.