الفيزياء العامة الجزء الثاني#موقع الفيزياء.كوم

Lectures in General Physics
The current I and the charge q are varying with time. Substitute for
dq
I = dt
(8.12)
dq q
ζ − R − = 0
(8.13)
dt C
By solving the differential equation to find the q as a function of time we
get,
−t
RC
q = Cζ (1 − e )
(8.14)
The quantity Cξ is the maximum charge Q in the capacitor.
−t
RC
q = Q(1
− e )
(8.15)
The current I is
I
=
dq
dt
ζ
= e
R
−t
RC
(8.16)
Q
q
I (A)
I o
Q = Cξ
I o
ξ
=
R
t (sec)
t (sec)
Figure 8.19
Plots of the charge Q and the current I as a function of
time in the charging process
Dr. Hazem Falah Sakeek