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Maxwell's equations
∇
×
E
=
−
∂
B
∂
t
\bm\nabla\times \bm E = -\frac{\partial\bm B}{\partial t}
∇
×
E
=
−
∂
t
∂
B
∇
×
H
=
J
+
∂
D
∂
t
\bm\nabla\times \bm H = \bm J + \frac{\partial \bm D}{\partial t}
∇
×
H
=
J
+
∂
t
∂
D
∇
⋅
D
=
ρ
\bm \nabla\cdot D = \rho
∇
⋅
D
=
ρ
∇
B
=
0
\bm\nabla\bm B = 0
∇
B
=
0
The Conservation Equation
∇
⋅
J
+
∂
ρ
∂
t
=
0
\bm \nabla\cdot\bm J + \frac{\partial\rho}{\partial t} = 0
∇
⋅
J
+
∂
t
∂
ρ
=
0
Potentials
V
(
r
,
t
)
=
1
4
π
ϵ
0
∫
ρ
(
r
′
,
t
−
R
c
)
R
d
v
′
=
1
4
π
ϵ
0
∫
ρ
r
e
t
R
d
v
′
V(\bm r, t) = \frac 1{4\pi\epsilon_0}\int\frac{\rho\left(\bm r', t-\frac Rc\right)}{R}\: dv' = \frac 1{4\pi\epsilon_0}\int\frac{\rho_{ret}}R\: dv'
V
(
r
,
t
)
=
4
π
ϵ
0
1
∫
R
ρ
(
r
′
,
t
−
c
R
)
d
v
′
=
4
π
ϵ
0
1
∫
R
ρ
re
t
d
v
′
A
(
r
,
t
)
=
μ
0
4
π
∫
J
(
r
′
,
t
−
R
c
)
R
d
v
′
=
μ
0
4
π
∫
J
r
e
t
R
d
v
′
\bm A(\bm r, t) = \frac{\mu_0}{4\pi}\int\frac{\bm J\left(\bm r', t - \frac Rc\right)}R\: dv' = \frac{\mu_0}{4\pi}\int\frac{\bm J_{ret}}R\: dv'
A
(
r
,
t
)
=
4
π
μ
0
∫
R
J
(
r
′
,
t
−
c
R
)
d
v
′
=
4
π
μ
0
∫
R
J
re
t
d
v
′
B
=
∇
×
A
\bm B = \bm\nabla\times\bm A
B
=
∇
×
A
E
=
−
∇
V
−
∂
A
∂
t
\bm E = -\bm\nabla V - \frac{\partial \bm A}{\partial t}
E
=
−
∇
V
−
∂
t
∂
A
Magnetic Flow Density
B
(
r
,
t
)
=
μ
0
4
π
∫
J
r
e
t
×
e
R
R
2
d
v
′
+
μ
0
4
π
c
∫
J
r
e
t
′
×
e
R
R
d
v
′
\bm B(\bm r, t) = \frac{\mu_0}{4\pi}\int \frac{\bm J_{ret}\times\bm e_R}{R^2}\: dv' + \frac{\mu_0}{4\pi c}\int\frac{\bm J'_{ret}\times \bm e_R}{R}\: dv'
B
(
r
,
t
)
=
4
π
μ
0
∫
R
2
J
re
t
×
e
R
d
v
′
+
4
π
c
μ
0
∫
R
J
re
t
′
×
e
R
d
v
′
Filamentuos Antenna
B
=
μ
0
4
π
∫
i
(
z
,
t
−
R
/
c
)
d
l
×
e
R
R
2
+
μ
0
4
π
c
∫
i
(
z
,
t
−
R
/
c
)
d
l
×
e
R
R
\bm B = \frac{\mu_0}{4\pi}\int \frac{i(z, t - R/c)d\bm l\times\bm e_R}{R^2} + \frac{\mu_0}{4\pi c}\int\frac{i(z, t - R/c)d\bm l\times \bm e_R}{R}
B
=
4
π
μ
0
∫
R
2
i
(
z
,
t
−
R
/
c
)
d
l
×
e
R
+
4
π
c
μ
0
∫
R
i
(
z
,
t
−
R
/
c
)
d
l
×
e
R
Oscillating Electric Dipole
B
=
μ
0
4
π
p
′
(
t
−
R
/
c
)
×
e
R
R
2
+
μ
0
4
π
c
p
′
′
(
t
−
R
/
c
)
×
e
R
R
\bm B = \frac{\mu_0}{4\pi} \frac{\bm p'(t - R/c)\times\bm e_R}{R^2} + \frac{\mu_0}{4\pi c}\frac{\bm p''(t - R/c)\times\bm e_R}R
B
=
4
π
μ
0
R
2
p
′
(
t
−
R
/
c
)
×
e
R
+
4
π
c
μ
0
R
p
′′
(
t
−
R
/
c
)
×
e
R
Oscillating Magnetic Dipole
B
=
−
μ
0
4
π
m
′
(
t
−
R
/
c
)
×
e
R
R
2
−
μ
0
4
π
c
m
′
′
(
t
−
R
/
c
)
×
e
R
R
\bm B = -\frac{\mu_0}{4\pi} \frac{\bm m'(t - R/c)\times\bm e_R}{R^2} - \frac{\mu_0}{4\pi c}\frac{\bm m''(t - R/c)\times\bm e_R}R
B
=
−
4
π
μ
0
R
2
m
′
(
t
−
R
/
c
)
×
e
R
−
4
π
c
μ
0
R
m
′′
(
t
−
R
/
c
)
×
e
R
Pointing's Vector
P
S
(
r
,
t
)
=
E
(
r
,
t
)
×
H
(
r
,
t
)
\bm P_S(\bm r, t) = \bm E(\bm r, t)\times\bm H(\bm r, t)
P
S
(
r
,
t
)
=
E
(
r
,
t
)
×
H
(
r
,
t
)