Density in fluid mechanics
The mass-to-volume ratio of a substance, essential for predicting buoyancy and behavior in fluids.
Specific gravity
A dimensionless ratio comparing a substance's density to the density of a reference substance, usually water at 4°C.
Density calculation formula
An equation represented as ρ = m/V, where ρ denotes density, m symbolizes mass, and V indicates volume.
Pressure in fluids
The magnitude of force exerted per unit area, mathematically expressed as P = F/A.
Pressure change in a fluid at rest
Describes how pressure varies with depth in a stationary fluid due to the weight of the fluid column above.
Pascal's Principle
States that an applied pressure change to an enclosed fluid is transmitted undiminished throughout the fluid.
Significance of Pascal's Principle
This principle is foundational for hydraulic mechanisms, enabling force multiplication in systems like hydraulic brakes.
Archimedes' Principle
Declares that an object submerged in a fluid will experience a buoyant force equal to the weight of the fluid displaced.
Float or sink determination
Determines an object's buoyancy based on its density relative to the fluid's density; it will float if less dense and sink if more dense.
Buoyancy
The upward force exerted by a fluid on a submerged object, counterbalancing the object's weight.
Fluid dynamics
The branch of physics that studies the behavior of fluids in motion, addressing forces, velocities, and flow characteristics.
Continuity Equation formula
Expressed as A1v1 = A2v2, indicating that the product of a fluid's cross-sectional area (A) and flow velocity (v) remains constant.
Bernoulli's Equation purpose
Illustrates the conservation of energy in fluid flow, asserting that total mechanical energy stays constant along a streamline.
Bernoulli's Equation formula
The mathematical representation as P + 0.5ρv² + ρgh = constant, encompassing pressure, density, velocity, and height.
Viscosity
A quantitative measure of a fluid's internal resistance to flow, reflecting intermolecular friction.
Effect of viscosity on fluid flow
Indicates that higher viscosity results in slower flow rates, while lower viscosity allows for quicker fluid movement.
Newton’s Law of Viscosity
Expressed as F=η(AΔv/d), where η is dynamic viscosity, A is surface area, Δv is the velocity change, and d is distance.
Laminar flow characteristics
Fluid movement where layers flow smoothly and parallel, exhibiting low turbulence and high order.
Turbulent flow characteristics
Fluid motion characterized by chaotic and irregular patterns, with vortices and eddies, typically occurring at high velocities.
Reynolds number
A non-dimensional number that helps predict flow regime as either laminar or turbulent, based on the ratio of inertial to viscous forces.
Reynolds number for laminar flow
Indicates that laminar flow typically occurs when the Reynolds number is below the threshold of 2000.
Reynolds number for turbulent flow
Denotes that turbulent flow generally takes place when the Reynolds number exceeds 4000.
Surface tension
A physical property that arises from cohesive forces at the surface of a liquid, causing it to behave as if covered by a stretched elastic membrane.
Phenomena caused by surface tension
Includes effects like droplet formation and the ability for certain small insects to traverse the liquid surface.
Capillary action
The phenomenon where liquid rises or falls in narrow spaces without external forces, driven by adhesive and cohesive intermolecular forces.
Factors affecting liquid rise in capillary action
Determined by the tube's radius and the liquid's surface tension, impacting how high the liquid will rise or fall.
Hydrostatic equilibrium
A state of balance in a fluid at rest, where all forces acting on the fluid are equal, resulting in no net fluid movement.
Regulation of fluid behavior in containers
The principles of hydrostatic equilibrium are critical for predicting and analyzing the behavior of fluids in both containers and natural bodies of water.
Fluid statics
The study focused on fluids at equilibrium, examining pressure distribution, buoyancy, and the forces affecting static fluids.
Purpose of pressure gauges
Devices designed to measure the pressure of gases or liquids, providing vital data for various applications and processes.
Function of a barometer
An instrument that quantifies atmospheric pressure, essential for meteorological applications and altitude measurement.
Types of pressure measured by gauges
Including absolute pressure, gauge pressure, and differential pressure, tailored to the requirements of specific applications.
Effect of temperature on viscosity
Generally, increasing temperature leads to a reduction in viscosity, altering the flow behaviors of fluids.
Applications of fluid mechanics
The concepts of fluid mechanics are utilized in various fields, such as hydraulic systems design, aerodynamics, and understanding atmospheric dynamics.
Buoyancy in engineering
Critical for ensuring that vessels like ships and submarines remain stable and function effectively on or below the water's surface