Hydraulics and Buoyancy — Vocabulary Flashcards (OpenStax University Physics Notes)

Vocabulary flashcards covering fluids, density, mass, volume, Pascal’s Principle, hydraulic systems, fluid pressure, Archimedes’ Principle, buoyancy, and related examples from the lecture notes.

Fluid

Any substance that can flow and take the shape of its container.

Density

Mass per unit volume of a substance.

Mass

The amount of matter in an object.

Volume

The amount of space that an object or fluid occupies.

Pascal’s Principle (Pascal’s Law)

In an enclosed, incompressible fluid, a pressure change is transmitted undiminished to all parts of the fluid and to the walls of its container.

Pressure

Force per unit area exerted by a fluid.

Enclosed Fluid

A fluid contained in a closed system where pressure can be increased by applying force.

Open System

A fluid that is not confined, so applying pressure can push the fluid to flow away (e.g., a river).

Hydraulic System

A system that uses pressurized fluid to transmit and amplify forces.

Pump

A device that pressurizes the fluid in a hydraulic system.

Fluid Reservoir

A tank that stores hydraulic fluid.

Tubes and Valves

Components that control the flow of hydraulic fluid.

Car Brakes (Hydraulic Brake System)

Brake force is transmitted via fluid lines; pressure is applied evenly to brakes due to Pascal’s principle.

Dentist Chair / Barber Chair (Hydraulic Chair)

A foot pedal pumps fluid to raise or lower the chair; pressure is distributed to lift the person.

Transmission of Pressure

In a hydraulic system, pressure applied to enclosed fluid is transmitted undiminished to all parts and walls.

Fluid Pressure

The force per unit area exerted by a fluid; increases with depth and can be transmitted in all directions.

Archimedes’ Principle

The buoyant force on an object equals the weight of the fluid displaced by the object.

Buoyant Force

The upward force on any object immersed in a fluid.

Buoyancy

Phenomenon by which objects float, sink, or suspend due to buoyant force.

Submarine Ballast Tanks

Adjustable ballast to change density and control floatation and sinking.

Density and Buoyancy Relationship

An object floats if its average density is less than the density of the surrounding fluid.

Mass-Displacement vs Volume-Displacement (Archimedes’ Principle Application)

A floating object displaces fluid equivalent in weight to its own mass; a sinking object displaces fluid equal to its total volume.

Syringe Pressure

Pushing the plunger increases pressure inside the syringe, forcing fluid out mainly due to small tip area.

Straw Pressure

Lowering the internal air pressure in a straw causes the liquid to rise due to higher external fluid pressure.