Properties of Fluids Get started with the basics — understand density, viscosity, surface tension, and compressibility. This section sets the foundation for everything that flows! 1 / 20 The phenomenon of a liquid rising or falling in a narrow tube is called: Capillarity Viscosity Fluidity Adhesion Capillary action occurs due to the combined effect of surface tension and adhesive forces. 2 / 20 The unit of surface tension in SI system is: N/m N·s/m² kg/m³ m²/s Surface tension is the force per unit length acting along the surface of a liquid. 3 / 20 A fluid that obeys Newton’s law of viscosity is called: Newtonian fluid Ideal fluid Non-Newtonian fluid Compressible fluid Newtonian fluids have a linear relationship between shear stress and velocity gradient. 4 / 20 The ratio of absolute viscosity to kinematic viscosity gives: Density Surface tension Compressibility Fluidity Kinematic viscosity = Dynamic viscosity / Density, hence rearranging gives density. 5 / 20 The fluid property that resists the relative motion between adjacent layers is: Adhesion Viscosity Surface tension Elasticity Viscosity represents internal friction between fluid layers moving at different velocities. 6 / 20 The force of adhesion is between: Two liquid layers Liquid and gas Solid and solid Liquid and solid Adhesion occurs when a liquid sticks to a solid surface — it causes wetting behavior. 7 / 20 Which fluid property defines its ability to transmit pressure equally in all directions? Density Surface tension Viscosity Incompressibility A truly incompressible fluid can transmit pressure equally throughout its volume (Pascal’s Law). 8 / 20 Bernoulli’s equation is derived from the law of: Conservation of pressure Conservation of energy Conservation of mass Conservation of momentum Bernoulli’s principle relates pressure, velocity, and elevation for incompressible flow using energy conservation. 9 / 20 Continuity equation is based on the principle of: Conservation of mass Conservation of momentum Conservation of energy Conservation of volume The continuity equation states that mass entering and leaving a control volume must remain constant. 10 / 20 The pressure at a point in a static fluid acts: Vertically downward Horizontally only Equally in all directions Normal to the boundary only In a static fluid, pressure is isotropic — acting equally in all directions. 11 / 20 A fluid that has no viscosity is known as: Non-Newtonian fluid Newtonian fluid Real fluid Ideal fluid An ideal fluid is a simplified concept used in theoretical analysis to neglect viscosity effects. 12 / 20 The SI unit of dynamic viscosity is: N·s/m² kg/m³ m²/s Pa/m Dynamic viscosity quantifies internal resistance to flow, with its SI unit as N·s/m² (or Pa·s). 13 / 20 The ratio of dynamic viscosity to density is called: Specific gravity Kinematic viscosity Surface tension Fluidity Kinematic viscosity relates the viscous forces to the fluid’s inertia and is expressed in m²/s. 14 / 20 Which property of fluid changes with temperature most significantly? Viscosity Density Specific weight Surface tension Viscosity decreases with an increase in temperature for liquids, making flow easier. 15 / 20 The mass of a fluid per unit volume is called: Density Specific weight Surface tension Viscosity Surface tension acts along the interface between liquid and air, causing capillary rise or depression. 16 / 20 Which fluid property is responsible for the rise of liquid in a capillary tube? Viscosity Surface tension Density Specific weight Surface tension acts along the interface between liquid and air, causing capillary rise or depression. 17 / 20 Which of the following is a dimensionless quantity? Dynamic viscosity Kinematic viscosity Density Specific gravity Specific gravity is a pure ratio of densities, so it has no units. 18 / 20 Which of the following statements is true for an ideal fluid? It can be compressed easily It cannot flow It has viscosity but no density It is incompressible and has no viscosity An ideal fluid is theoretical — it cannot be compressed and has zero viscosity for simplified analysis. 19 / 20 The ratio of the weight of a given volume of fluid to the weight of an equal volume of water at 4°C is called: Viscosity Specific weight Specific gravity Density Specific gravity compares the density of a fluid to that of water, making it dimensionless. 20 / 20 Which of the following properties defines the resistance of a fluid to shear deformation? Density Viscosity Compressibility Specific weight Viscosity measures a fluid’s internal resistance to motion or flow — higher viscosity means thicker flow. Your score isThe average score is 55% 0% Restart quiz