What is the primary force responsible for buoyancy?
A Viscous force
B Gravitational force
C Surface tension
D Inertial force
Buoyancy is the upward force exerted on an object submerged in a fluid due to the pressure difference caused by gravity. It is calculated using Archimedes’ principle, which states that the buoyant force equals the weight of the displaced fluid.
What is the unit of kinematic viscosity?
A m²/s
B N/m²
C kg/m³
D m/s²
Kinematic viscosity is the ratio of dynamic viscosity to fluid density. Its SI unit is m²/s. It represents the fluid’s resistance to flow under the influence of gravity.
Which equation describes the conservation of momentum in fluid flow?
A Bernoulli’s equation
B Continuity equation
C Navier Stokes equation
D Euler’s equation
The Navier Stokes equations describe the motion of viscous fluid substances. They account for forces such as pressure, viscosity, and external forces, providing a mathematical model for fluid flow.
What is the primary purpose of a manometer?
A Measure flow rate
B Measure velocity
C Measure pressure
D Measure viscosity
A manometer is a device used to measure fluid pressure by balancing the fluid column against a known pressure. It is commonly used in laboratories and industries for accurate pressure measurements.
What is the critical Reynolds number for flow in a pipe?
A 500
B 2000
C 1000
D 4000
The critical Reynolds number for pipe flow is approximately 2000. Below this value, the flow is laminar; above 4000, it is turbulent. Between 2000 and 4000, the flow is transitional.
What is the primary cause of drag force in fluid flow?
A Viscosity
B Pressure difference
C Surface tension
D Gravity
Drag force is caused by the resistance of a fluid to the motion of an object. Viscosity creates shear stress, which opposes the relative motion between the fluid and the object.
What is the primary application of a Pitot tube?
A Measure pressure
B Measure velocity
C Measure flow rate
D Measure viscosity
A Pitot tube measures fluid flow velocity by converting the kinetic energy of the flow into potential energy (pressure difference). It is widely used in aerodynamics and fluid mechanics.
What is the primary assumption in Euler’s equation?
A Viscous flow
B Incompressible flow
C Inviscid flow
D Turbulent flow
Euler’s equation assumes inviscid (frictionless) flow, neglecting viscous forces. It is derived from Newton’s second law and is used to analyze fluid motion in ideal conditions.
What is the primary purpose of a siphon?
A Transfer fluid between reservoirs
B Measure flow rate
C Increase pressure
D Reduce velocity
A siphon is a tube used to transfer liquid from a higher level to a lower level over an intermediate elevation. It works based on the principles of gravity and pressure difference.
What is the primary cause of lift force on an airfoil?
A Viscosity
B Surface tension
C Gravity
D Pressure difference
Lift force is generated due to the pressure difference between the upper and lower surfaces of an airfoil. The shape of the airfoil causes faster flow on the top, reducing pressure and creating lift.
What is the primary purpose of dimensional analysis?
A Simplify complex problems
B Measure fluid density
C Calculate fluid pressure
D Determine fluid temperature
Dimensional analysis reduces the number of variables in a problem by identifying dimensionless groups (e.g., Reynolds number). It simplifies the analysis of fluid flow and other physical phenomena.
What is the primary cause of surge in pipelines?
A Increase in fluid density
B Decrease in fluid velocity
C Increase in fluid temperature
D Sudden valve opening
Surge in pipelines is caused by sudden changes in flow velocity, such as when a valve is opened or closed abruptly. This creates pressure waves that can damage the pipeline.
What is the primary purpose of a turbine in fluid systems?
A Increase fluid pressure
B Measure fluid flow
C Convert fluid energy to mechanical energy
D Store fluid
A turbine extracts energy from a fluid (water, steam, or gas) and converts it into mechanical energy, which is then used to generate electricity or perform other work.
What is the primary cause of boundary layer separation?
A Increase in fluid velocity
B Adverse pressure gradient
C Decrease in fluid viscosity
D Increase in fluid temperature
Boundary layer separation occurs when the fluid flow slows down due to an adverse pressure gradient, causing the flow to detach from the surface and form eddies or vortices.
What is the primary purpose of flow visualization techniques?
A Study flow patterns
B Measure fluid pressure
C Calculate fluid velocity
D Determine fluid density
Flow visualization techniques, such as dye injection or smoke tracing, are used to observe and analyze the behavior of fluid flow, including patterns, turbulence, and boundary layer effects.