Equations · equation
Ampère–Maxwell Law
Electromagnetism · 1861
- Equation
- ∇×B = μ₀J + μ₀ε₀·∂E/∂t
- Field
- Electromagnetism
- Named After
- André-Marie Ampère · James Clerk Maxwell
- Symbols
- B magnetic field · J current density · E electric field · μ₀ permeability of free space · ε₀ permittivity of free space · t time
- Year
- 1861
Significance
Currents make magnetic fields — and, Maxwell's crucial addition, so do changing electric fields. That extra term closes the loop: E and B can regenerate each other and race through empty space as light, at exactly c. Fourth of Maxwell's equations, completing the set with Gauss's two laws and Faraday's.
Referenced by
constant
equation
machine
theory
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