Page:Elementary lectures on electric discharges, waves and impulses, and other transients (Steinmetz 1911).djvu/27

 To produce the magnetic field $$\Phi$$ of the current $$i$$, a voltage $$e'$$ must be consumed in the circuit, which with the current $$i$$ gives the power $$p$$, which supplies the stored energy $$w$$ of the magnetic field $$\Phi$$. This voltage $$e'$$ is called the inductance voltage, or voltage consumed by self-induction.

or by (1),

$$

or by (2) and (4),

$$

hence

$$

is the energy of the magnetic field

$$

of the circuit.

To produce the dielectric field $$\mathit\Psi$$ of the voltage $$e$$, a current $$i'$$ must be consumed in the circuit, which with the voltage $$e$$ gives