Fluids

What is pressure in physics?

Pressure is defined as the force applied per unit area in a direction perpendicular to the surface of an object.

What is Pascal's principle?

Pascal's principle states that a change in pressure applied to an enclosed fluid is transmitted undiminished to every point of the fluid and to the walls of its container.

How does height affect fluid pressure?

Fluid pressure increases with depth due to the weight of the fluid above; specifically, it increases approximately 0.1 atmospheres for every 10 meters of water depth.

What is buoyancy?

Buoyancy is the upward force exerted by a fluid on an object placed in it, allowing objects to float.

What is Archimedes' principle?

Archimedes' principle states that a body immersed in a fluid experiences a buoyant force equal to the weight of the fluid it displaces.

Define density in relation to fluids.

Density is the mass per unit volume of a substance, commonly expressed in kilograms per cubic meter (kg/m³) in fluids.

What is hydrostatic pressure?

Hydrostatic pressure is the pressure exerted by a fluid at equilibrium due to the force of gravity acting on it.

What role does surface tension play in fluids?

Surface tension is the cohesive force at the surface of a liquid that causes it to behave as if its surface is covered with a stretched elastic membrane.

Explain the concept of laminar flow.

Laminar flow is characterized by smooth, orderly fluid motion where layers of fluid slide past each other without mixing.

What is turbulent flow?

Turbulent flow is a type of fluid flow characterized by chaotic, irregular motion, where fluid particles move in various directions and velocities.

What is fluid dynamics?

Fluid dynamics is the study of the behavior of fluids in motion, analyzing how forces affect fluid flow.

What is the Bernoulli's equation?

Bernoulli's equation relates the pressure, velocity, and height of a fluid in steady flow, stating that an increase in fluid speed decreases pressure or potential energy.

What is gauge pressure?

Gauge pressure is the pressure relative to atmospheric pressure, commonly used in measuring tire pressure or pressure in pipes.

What is absolute pressure?

Absolute pressure is the total pressure exerted by a fluid, measured relative to a perfect vacuum.

What is a fluid?

A fluid is a substance that can flow and take the shape of its container, including liquids and gases.

How does temperature affect fluid viscosity?

As temperature increases, fluid viscosity typically decreases, allowing fluids to flow more easily.

What is the difference between incompressible and compressible fluids?

Incompressible fluids have constant density regardless of pressure changes, while compressible fluids have variable density affected by pressure changes.

What is centripetal force in terms of fluids?

In fluid dynamics, centripetal force is needed to keep fluid particles moving in a circular path, acting towards the center of rotation.

What is the principle of continuity?

The principle of continuity states that for an incompressible fluid, the mass flow rate must remain constant from one cross-section of a pipe to another.

What is viscosity?

Viscosity is the measure of a fluid's resistance to flow or deformation, indicating how thick or sticky a fluid is.

What formula is used to calculate pressure?

Pressure (P) = Force (F) / Area (A)

If a cylindrical container has a radius of 2 m and a height of 5 m, what is the area of the base?

Area = π * radius² = π * (2 m)² = 12.57 m².

How do you calculate the buoyant force acting on an object?

Buoyant Force = Weight of the fluid displaced = volume of the object submerged * density of the fluid * g.

A fluid has a density of 800 kg/m³. What is the pressure at a depth of 10 m?

Pressure = density * g * height = 800 kg/m³ * 9.81 m/s² * 10 m = 78,480 Pa.

What is the principle behind Archimedes' principle?

An object submerged in fluid experiences a buoyant force equal to the weight of the fluid it displaces.

If a fluid's temperature rises, how does it generally affect viscosity?

Viscosity typically decreases as the temperature of the fluid rises.

In a closed system, how does pressure change if the volume is halved?

According to Boyle's Law, if volume decreases, pressure increases if temperature is constant.

What is the equation for Bernoulli's principle?

P + ½ρv² + ρgh = constant, where P = pressure, ρ = density, v = velocity, g = acceleration due to gravity, h = height.

What happens to the pressure in a pipe as the diameter narrows?

According to the principle of continuity, pressure decreases as the fluid velocity increases in a narrower section.

If a tire has a gauge pressure of 30 psi, what is its absolute pressure assuming atmospheric pressure is 14.7 psi?

Absolute pressure = Gauge pressure + Atmospheric pressure = 30 psi + 14.7 psi = 44.7 psi.