Scientific Ontology

A

Mechanics

Area

Extent of a two-dimensional surface.

square metre (m²)

Dimension: $[\,L^2\,]$

How values of area span the physical world (in m², log scale).

Atomic cross-section

10^-20 m²

A4 sheet

6.20 × 10^-2 m²

Football pitch

7.00 × 10³ m²

Lower limit10^-28 m²Upper limit10¹⁴ m²

Pressure

p = \dfrac{F}{A}

Magnetic Flux

\Phi = B A \cos\theta

Tensile Stress

\sigma = \dfrac{F}{A}

Resistivity

R = \dfrac{\rho l}{A}

Stefan–Boltzmann Law

L = \sigma A T^4

Intensity

I = \dfrac{P}{A}