Pressure and Buoyancy - JSS2 Basic technology Past Questions and Answers - page 2

Pressure is the force per unit area applied perpendicular to a surface, represented as ( P = F / A ). Its SI unit is the Pascal (Pa), equivalent to one Newton per square metre (N/m²).

High pressure compresses materials, while low pressure allows expansion. Continuous high pressure can stress materials, potentially compromising their structural integrity. This is crucial in designing buildings and aircraft to withstand various pressure.

Archimedes' Principle states that a submerged object experiences an upward buoyant force equal to the weight of the displaced fluid. It explains why objects float or sink based on their density relative to the fluid.

Pressure and volume are inversely proportional; increasing pressure compresses a gas, decreasing its volume, and vice versa. This principle is evident in compressed air storage, lung function during breathing, and aircraft cabin pressurisation.

Hydrometers measure liquid density using buoyancy, floating at different depths based on liquid density. The hydrometer sinks more in less dense liquids and less in denser ones, with a scale indicating density.