Physics Ontology

One map of physics, three ways in. Drill down on any quantity to see its units, the equations it lives in, and how its values span the universe.

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Optics

Focal Length

Distance from a lens to its focal point.

SI unit

metre (m)

Dimension: [ L ][\,L\,]

Other units

  • metre (m)

Order of magnitude

How values of focal length span the physical world (in m, log scale).

Camera lens
5.00 × 10-2 m
Reading glasses
5.00 × 10-1 m
Lower limit10-3 mUpper limit100 m

Appears in 1 equation

Thin Lens Equation
1u+1v=1f\dfrac{1}{u} + \dfrac{1}{v} = \dfrac{1}{f}