29. The. Basic Formulas of Electrodynamics in the SI
and Gaussian Systems
Name
SI
Gaussian system
Strength of the
field of a point
charge
Strength of the
field of a plane
Potential of the
field of a point
Relation between
E and y
Electric dipole p
in field E
Relation between
Relation between
a', P, and E
Definition of the
vector D
Relation between
a and x
Relation between
Gauss theorem for
the vector D
Capacitance of a
capacitor
Capacitance of a
plane capacitor
Energy of a system of charges
Energy of a capacitor
Energy density of
electric field
Ohm's law
Joule's law
Magnetic moment
of a current carrying loop
Magnetic dipole
pm in the field B
E—
1
q
— (P2=
iv= _pE
gy
2 qi(Pi
CV2 /2
1
aE2
W = —
j=crE
4xrcr
E =43-re, r2
0
E = -capacitor
808
1
q
a
q
r
2
.S' Eici/
1
P= xE
Q' = 13 7i = xEn
D=E+43TP
e=1+4ax
D=8E
(1 DnelS=4aq
eS
charge
P and E
D and E
IT=
—
43-teo r
E= — Vc1), ( P i
N=[pE],
P= xe0E
O f = Pn =xeoEn
D=e0E-FP
8=1+x
D =808E
§ DndS=q
C --C—
EoaS
d
W=1/2
W --- -
ED
w=
,C- 4ad
w—
= — 8
D
2
w=
pm = /S
N= [pm13],
- 37 1,
1 IS
Pm=7
pmB