Fluid Mechanics and Pressure Flashcards

Vocabulary flashcards covering pressure, Pascal's principle, fluid properties, intermolecular forces, Archimedes' principle, density, and buoyancy based on lecture notes.

Pressure ($P$)

The force exerted per unit area, calculated using the formula $P = \frac{F}{A}$.

Pascal ($Pa$)

The SI unit of pressure, equivalent to one Newton per square meter ($1\,Pa = 1\,N/m^2$).

Newton ($N$)

The SI unit of force ($F$) used in calculating pressure.

Ocean Pressure

The pressure value associated with the ocean in the lecture notes, recorded as $4066\,atm$.

Earth Core Pressure

The pressure at the Earth's center noted in the transcript, given as $3.6\text{ mil }atm$.

Hydraulic System

A mechanism consisting of a small piston and a large piston that transmits and multiplies force ($F$), allowing a smaller force to be applied on the small piston because pressure is transmitted equally.

Pascal's Principle

Also known as Pascal's law, it states that a change in pressure applied to an enclosed fluid is transmitted equally and undiminished to all portions of the fluid and the walls of its container.

Enclosed Fluid

A fluid that is completely confined within a container or pipe.

Undiminished Transmission

The characteristic of fluid pressure transmission meaning it does not lose strength or reduce in magnitude throughout the fluid.

Fluid

A liquid or gas that deforms continuously under applied pressure or stress.

Incompressibility

A fluid property characterized by resistance to changes in volume when pressure is applied.

Compressibility

A fluid property that allows its volume to decrease under applied pressure.

Viscosity

The internal resistance of a fluid to flow, caused by internal friction.

Cohesion

Intermolecular forces (IMFA) existing between molecules within the same fluid.

Adhesion

Intermolecular forces (IMFA) existing between fluid molecules and solid surface molecules.

Surface Tension

A phenomenon caused by unbalanced cohesive forces at a fluid's surface, causing it to behave like a stretched elastic membrane.

Buoyancy

The upward force exerted by a fluid that supports an object placed in it.

Archimedes' Principle

A principle dating to the 3rd century BCE (associated with 'Eureka') stating that the volume of water displaced by a submerged object equals the volume of the object submerged, and the buoyant force equals the weight of the fluid displaced.

Buoyant Force

The actual upward force acting on an object submerged in a fluid.

Water Displacement

The movement of water caused by submerging an object in it.

Mass

A scalar quantity measured in $kg$; as mass increases, weight increases, requiring the object to displace enough fluid to equal its weight to float.

Density ($\rho$)

The ratio of mass to volume, calculated as $\rho = \frac{m}{V}$ and measured in $kg/m^3$.

Weight Force ($w$)

The downward force acting on an object due to gravity, calculated as $w = mg$.

Floating Condition

Occurs when an object is less dense than the fluid, or when the upward buoyant force equals the downward weight force ($\text{Buoyant Force} = \text{Weight}$), resulting in a net force of zero.

Sinking Condition

Occurs when an object is more dense than the fluid, or when the buoyant force is less than the downward weight force ($\text{Buoyant Force} < \text{Weight}$), causing the object to move downward.

Suspended Condition

Occurs when an object's density is equal to the fluid's density, causing it to remain suspended within the fluid.

Fluid Pressure

Pressure exerted per unit area by a fluid that acts upward and increases with depth.

Shape-Volume-Displacement Sequence

The causal chain in buoyancy where changing an object's shape changes its volume, volume changes fluid displacement, and displacement changes the buoyant force.