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Formula 4. Maxwell Equation of Electrostatics in Integral Form Magnetic field    Electric current    Vacuum permeability

Formula
Formula: 4. Maxwell Equation of Electrostatics in Integral Form
Current Generates Rotating Magnetic Field

Magnetic field

Unit
Magnetic flux density determines the force on a moving electric charge.

Maxwell's fourth equation of electrostatics states that an electric current \(I\) causes a rotating magnetic field \(B\) and vice versa.

Closed loop

Unit
A closed loop (e.g. a circle) along which the magnetic field \(B\) is summed up by means of the line integral.

Here \( \text{d}\boldsymbol{l} \) is a small line element of the loop. The direction of \(\text{d}\boldsymbol{l}\) points tangential to the loop at each point on the loop.

Electric current

Unit
Electric current enclosed by the loop \(L\).

Vacuum permeability

Unit
The vacuum permeability is a physical constant and has the following experimentally determined value:$$ \mu_0 ~=~ 1.256 \, 637 \, 062 \, 12 ~\cdot~ 10^{-6} \, \frac{\mathrm{Vs}}{\mathrm{Am}} $$