Scientific Ontology

E

Mechanics

Energy

Capacity to do work; conserved across all interactions.

joule (J)

Dimension: $[\,M L^2 T^{-2}\,]$

How values of energy span the physical world (in J, log scale).

Single photon (visible)

3.00 × 10^-19 J

Beating heart (per beat)

10⁰ J

Lightning bolt

10⁹ J

Supernova

10⁴⁴ J

Lower limit10^-21 JUpper limit10⁴⁷ J

Kinetic Energy

E_k = \tfrac{1}{2} m v^2

First Law of Thermodynamics

\Delta U = Q - W

Planck–Einstein Relation

E = h f

Photoelectric Effect

E_k = h f - \phi

Mass–Energy Equivalence

E = m c^2

Elastic Strain Energy

\Delta E_{el} = \tfrac{1}{2} F \Delta x

Capacitor Energy Stored

W = \tfrac{1}{2} C V^2

Specific Heat Capacity

\Delta E = mc\,\Delta\theta

Latent Heat

\Delta E = L\Delta m