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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VV
Electromagnetism

Voltage

Electric potential difference between two points.

SI unit

volt (V)

Dimension: [ML2T3I1][\,M L^2 T^{-3} I^{-1}\,]

Other units

  • volt (V)
  • kilovolt (kV)×1.00e+3

Order of magnitude

How values of voltage span the physical world (in V, log scale).

Nerve cell
7.00 × 10-2 V
AA battery
1.50 × 100 V
Mains
2.30 × 102 V
Lightning
108 V
Lower limit10-6 VUpper limit109 V

Appears in 7 equations

Ohm's Law
V=IRV = I R
Electrical Power
P=VIP = V I
Capacitance
C=QVC = \dfrac{Q}{V}
Faraday's Law of Induction
ε=dΦdt\varepsilon = -\dfrac{d\Phi}{dt}
Capacitor Energy Stored
W=12CV2W = \tfrac{1}{2} C V^2
Electric Potential (point charge)
V=14πε0QrV = \dfrac{1}{4\pi\varepsilon_0}\dfrac{Q}{r}
RMS Voltage
Vrms=V02V_{\mathrm{rms}} = \dfrac{V_0}{\sqrt{2}}

Associated scientists