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22 ELECTRIC DISCHARGED WAVK8 AND

shown dotted in Fig. I16^y, The area of this new voltage* curve
would be 6₀r, and since it iB the Bame an that of tin* eurve «?, an
seen above, it follows that the area of the voltage eurvo c M

and, combining (2) and (3), to cancel^ and we get the value of 7¹:

That is, the initial decrease* of current, and therefore of mag-
netic flux and of induced voltage, in mieh that if the dwreaMe

continued at the- Bame rate, the current, (lux, and voltage would

become ^ero after the time T » - - •

The total induced voltage, that is, voltage time* Ume_t mid
therefore also the total current and magnetic* flux during the
transient, are such that, when maintained at their initial value,

they would last for the time T =» '•

Since the curves of current and voltage theoretically never
'become &ero, to get an estimate of the duration of the tmtiment
we may determine the time in which the trannient declines to
half, or to one-tenth, otc., of its initial value, It IH preferable,
however, to estimate the duration of the trannient by the time 7*,
which it would last if maintamwl at itH initial vahus That Ls»

the duration of a transient in coiwidi^red m the time Y¹*^ '-

This time T has frequently been culled the " twin (untMtant ^lfof the circuit.

The higher the inductance £, the long«*r the triuiHient
obviously, since the stored energy which the tnuiHiintt
'is proportional to L

The higher the resistance r, the nhorter IH tlw duration of ftit*
transient, since in the higher roHigbamw tin* Htcmnl onorKy I* »w>re
rapidly dissipated,

Using the time constant T - - m unit of langtli for the nlwiMHii,

and the initial value as unit of the ottiinattM, nil i»x|H>tunitial

transients have the same shape, and cun thereby \



	22 ELECTRIC DISCHARGED WAVK8 AND shown dotted in Fig. I16^y, The area of this new voltage* curve would be 6₀r, and since it iB the Bame an that of tin* eurve «?, an seen above, it follows that the area of the voltage eurvo c M and, combining (2) and (3), to cancel^ and we get the value of 7¹:

	That is, the initial decrease* of current, and therefore of mag- netic flux and of induced voltage, in mieh that if the dwreaMe continued at the- Bame rate, the current, (lux, and voltage would become ^ero after the time T » - - • r The total induced voltage, that is, voltage time* Ume_t mid therefore also the total current and magnetic* flux during the transient, are such that, when maintained at their initial value, they would last for the time T =» '• Since the curves of current and voltage theoretically never 'become &ero, to get an estimate of the duration of the tmtiment we may determine the time in which the trannient declines to half, or to one-tenth, otc., of its initial value, It IH preferable, however, to estimate the duration of the trannient by the time 7, which it would last if maintamwl at itH initial vahus That Ls» the duration of a transient in coiwidi^red m the time Y¹^ '- r This time T has frequently been culled the " twin (untMtant ^lfof the circuit. The higher the inductance £, the long«r the triuiHient obviously, since the stored energy which the tnuiHiintt 'is proportional to L The higher the resistance r, the nhorter IH tlw duration of ftit transient, since in the higher roHigbamw tin* Htcmnl onorKy I* »w>re rapidly dissipated, Using the time constant T - - m unit of langtli for the nlwiMHii, and the initial value as unit of the ottiinattM, nil i»x\|H>tunitial transients have the same shape, and cun thereby \