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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Electromagnetism

Magnetic Field

Magnetic flux density; force on moving charges and currents.

SI unit

tesla (T)

Dimension: [ MT−2I−1 ][\,M T^{-2} I^{-1}\,]

Other units

  • tesla (T)
  • gauss (G)×1.00e-4

Order of magnitude

How values of magnetic field span the physical world (in T, log scale).

Human brain
10-12 T
Earth's field
5.00 × 10-5 T
Fridge magnet
5.00 × 10-3 T
MRI scanner
3.00 × 100 T
Magnetar
1011 T
Lower limit10-15 TUpper limit1011 T

Appears in 5 equations

Lorentz Force
F⃗=q(E⃗+v⃗×B⃗)\vec{F} = q(\vec{E} + \vec{v} \times \vec{B})
Magnetic Flux
Φ=BAcos⁡θ\Phi = B A \cos\theta
Magnetic Force on a Wire
F=BIlsin⁡θF = BIl\sin\theta
Magnetic Force on a Moving Charge
F=Bqvsin⁡θF = Bqv\sin\theta
Radius in a Magnetic Field
r=pBqr = \dfrac{p}{Bq}

Associated scientists