What fluid characteristic is defined as the resistance to shearing forces________________?
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Answer: D. viscosity
Explanation
Viscosity is defined scientifically as a fluid property that quantifies its internal resistance to gradual shear or tensile stress. When adjacent layers of fluid move at different velocities, molecular cohesion and momentum transfer create a frictional shearing force. Fluids with high viscosity, such as heavy motor oil or honey, resist flow and deformation much more than low viscosity fluids. Dynamic viscosity measures shearing stress divided by the velocity gradient perpendicular to the direction of fluid motion. Kinematic viscosity is calculated by dividing dynamic viscosity by the fluid mass density at a given temperature. Temperature changes affect liquids and gases differently, decreasing liquid viscosity while increasing gas viscosity as temperature rises.
Surface tension describes the elastic tendency of liquid surfaces that makes them acquire the least surface area possible. Adhesion is the attractive force between dissimilar molecules, such as water clinging to the surface of glass tubing. Cohesion refers to the intermolecular attraction between like molecules within a substance, holding the fluid together rather than shearing.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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