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DOUBLE-ENERGY TRANSIENTS. 61

energy is dissipated before this. This latter case occurs when the
dissipation of energy is very rapid, the resistance (or conductance)
high, and therefore gives transients, which rarely are of industrial
importance, as they are of short duration and of low power. It
therefore is sufficient to consider the oscillating double-energy
transient, that is, the ease in which the energy changes periodically
between its two forms, during its gradual dissipation.

This may be done by considering separately the periodic trans-
fer, or pulsation of the energy between its two forms, and the
gradual dissipation of energy*

A. Pulsation of energy,

25. The magnetic, energy is a maximum at the moment when
the dielectric energy is ssoro, and when all the energy, therefore, is
magnetic; and the magnetic energy is then

where io »• maximum value of transient current.

The dielectric energy is a maximum at the moment when the
magnetic energy is ssero, and all the energy therefore dielectric,
and is then

Ceo²_,

where €Q «= maximum value of transient voltage.

As it is the same stored energy which alternately appears as
magnetic and as dielectric energy, it obviously is

l/i<o \>e$ /_Ov

-₂ --jj"- (8)

This given a relation between the maximum value of transient
current and the maximum value of transient voltage:

(9)

t»Q » V

v/i

therefore is of the nature of an impedance #o> and is called

the natural impedance, or the surge impedance, of the circuit; and

its reciprocal, y y » y^ is the natural admittance, or the surge
admittance, of the circuit-



	DOUBLE-ENERGY TRANSIENTS. 61 energy is dissipated before this. This latter case occurs when the dissipation of energy is very rapid, the resistance (or conductance) high, and therefore gives transients, which rarely are of industrial importance, as they are of short duration and of low power. It therefore is sufficient to consider the oscillating double-energy transient, that is, the ease in which the energy changes periodically between its two forms, during its gradual dissipation. This may be done by considering separately the periodic trans- fer, or pulsation of the energy between its two forms, and the gradual dissipation of energy* A. Pulsation of energy, 25. The magnetic, energy is a maximum at the moment when the dielectric energy is ssoro, and when all the energy, therefore, is magnetic; and the magnetic energy is then

	where io »• maximum value of transient current. The dielectric energy is a maximum at the moment when the magnetic energy is ssero, and all the energy therefore dielectric, and is then Ceo²_, where €Q «= maximum value of transient voltage. As it is the same stored energy which alternately appears as magnetic and as dielectric energy, it obviously is l/i<o \>e$ /_Ov -₂ --jj"- (8) This given a relation between the maximum value of transient current and the maximum value of transient voltage:

	(9) t»Q » V

	v/i	therefore is of the nature of an impedance #o> and is called

	the natural impedance, or the surge impedance, of the circuit; and Ic its reciprocal, y y » y^ is the natural admittance, or the surge admittance, of the circuit-