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Area Mathematics - Functions / Functions of one variable, mainly time-dependent quantities

IEV ref103-05-26

Symbol
τ

en
time constant
time τ in the expression F(t)=A+B e t/τ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAeacaGGOaGaam iDaiaacMcacqGH9aqpcaWGbbGaey4kaSIaamOqaKqzafGaciyzaOWa aWbaaSqabeaacqGHsislcaWG0bGaai4laiaads8aaaaaaa@419A@ of a quantity F growing or decaying exponentially towards a constant value A with increasing time t, or in the expression F(t)=A+f(t) e t/τ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAeacaGGOaGaam iDaiaacMcacqGH9aqpcaWGbbGaey4kaSIaamOzaiaacIcacaWG0bGa aiykaKqzafGaciyzaOWaaWbaaSqabeaacqGHsislcaWG0bGaai4lai abes8a0baaaaa@4489@ of an exponentially damped oscillation, where f is a periodic function of time

Note 1 to entry: The time constant of an exponentially varying quantity is the duration of a time interval at the end of which the absolute value of the difference between the quantity and the limit has decreased to 1/e of the absolute value of this difference at the beginning of the time interval, where e is the base of natural logarithms.

Note 2 to entry: The time constant of a damped oscillation is the inverse of the damping coefficient.


fr
constante de temps, f
temps τ dans l'expression F(t)=A+B e t/τ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAeacaGGOaGaam iDaiaacMcacqGH9aqpcaWGbbGaey4kaSIaamOqaKqzafGaciyzaOWa aWbaaSqabeaacqGHsislcaWG0bGaai4laiaads8aaaaaaa@419A@ d'une grandeur F croissant ou décroissant exponentiellement en fonction du temps t vers une valeur constante A, ou dans l'expression F(t)=A+f(t) e t/τ MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGe aGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaq Fn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpe WZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAeacaGGOaGaam iDaiaacMcacqGH9aqpcaWGbbGaey4kaSIaamOzaiaacIcacaWG0bGa aiykaKqzafGaciyzaOWaaWbaaSqabeaacqGHsislcaWG0bGaai4lai abes8a0baaaaa@4489@ d'une oscillation amortie exponentiellement, où f est une fonction périodique du temps

Note 1 à l'article: La constante de temps d'une grandeur variant exponentiellement est la durée d'un intervalle de temps au bout duquel la valeur absolue de la différence entre la grandeur et la limite atteint 1/e fois la valeur absolue de cette différence au début de l'intervalle de temps, où e est la base des logarithmes népériens.

Note 2 à l'article: La constante de temps d'une oscillation amortie est l'inverse du coefficient d'amortissement.


ar
الثابت الزمنى

de
Zeitkonstante, f

es
constante de tiempo

it
costante di tempo

ja
時定数

pl
stała czasowa

pt
constante de tempo

sr
временска константа, ж јд

sv
tidkonstant

zh
时间常数

Publication date: 2009-12
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