Reference Guide
5-14 Equation Reference
RLC Current Delay (2, 11)
The phase delay (angle) is positive for current lagging voltage.
Equations:
Example:
Given:
f= 1107_Hz, C=80_µf, L=20_ mH, R=5_Ω.
Solution:
ω
=672.3008_r/s,
φ
s= -45.8292_°,
φ
p= -5.8772_°, XC=18.5929_Ω, XL=13.4460_Ω.
DC Capacitor Current (2, 12)
These equations approximate the dc current required to charge the voltage on a capacitor in a certain time interval.
Equations:
I C
V∆
t∆
--------
⋅=
V∆ Vf– Vi–= t∆ tf ti⋅=
Example:
Given:
C=15_µf, Vi=2.3_V, Vf=3.2_ V, I=10_A, ti=0_s.
Solution:
∆V=0.9000_V, ∆t=1.3500_µs, tf=1.3500_µs.
Capacitor Charge (2, 13)
Equation:
q C V⋅=
Example:
Given:
C=20_µF, V=100_V.
Solution:
q=0.0020_C.
T
A
N
φ
s
(
)
X
L
X
C
–
R
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-
-
-
-
-
-
-
-
-
-
-
-
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-
-
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-
-
=
T
A
N
φ
p
(
)
1
X
C
-
-
-
-
-
-
-
-
1
X
L
-
-
-
-
-
-
-
-
–
1
R
-
-
-
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-
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-
-
-
-
-
-
-
-
-
-
-
-
-
-
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=
X
C
1
ω
C
⋅
-
-
-
-
-
-
-
-
-
-
-
-
=
X
L
ω
L
⋅
=
ω
2
π
f
⋅
⋅
=