What dimensionless or ratio parameter is defined as absolute viscosity divided by mass density_________________?
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Answer: C. kinematic viscosity
Explanation
Kinematic viscosity is explicitly defined as the ratio of dynamic viscosity to mass density. Dividing absolute viscosity by mass density yields a parameter with units of square meters per second. This dimensionless-like ratio characterizes fluid flow behavior where gravitational and inertial forces dominate viscous forces. Dynamic viscosity measures a fluid's internal resistance to shear flow under the influence of an applied force. Mass density represents the mass of fluid contained within a specified unit of volumetric space. Combining these two fundamental fluid properties creates kinematic viscosity, simplifying Navier-Stokes momentum equations.
Navier-Stokes equations frequently incorporate kinematic viscosity to analyze boundary layer development and pipe flow regimes. Aerospace and mechanical engineers use this property to calculate Reynolds numbers for aerodynamic and hydrodynamic testing. Lubricant selection for machinery relies heavily on knowing how kinematic viscosity changes with operating temperatures. Specific viscosity measures relative viscosity increases in dilute polymer solutions rather than pure fluid properties. Viscosity index represents an empirical rating of how much a lubricant's viscosity changes with temperature fluctuations. Coefficient of compressibility describes how fluid volume changes in response to uniform external pressure variations.
- Subject
- Engineering
- Category
- Mechanical Engineering
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- —
- Difficulty
- medium
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