ĐIỆN THẾ - HIỆU ĐIỆN THẾ docx


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


















 
 
!"#$"$
!"#$"$
E
r
E
r
%&'()
%&'()



E
r
F
r
F
r
*+",&
*+",&
A
A
MN
MN
= q.E.
= q.E.
= q.E.d
= q.E.d
MN
MN
♣
♣


)/-'0'1234
)/-'0'1234
5+6
5+6
♣
♣



7."58946
7."58946
♣
♣


'
'
:;
:;
.<=,>?
.<=,>?
@14"546
@14"546
'
'
:;
:;
AB=:
AB=:
→
→
;C
;C
'
'
:;
:;

DB=:
DB=:
→
→
;E
;E
♥
♥


2F4.
2F4.
A
A
MN
MN


!"@("
!"@("
'GH@("I)
'GH@("I)
,F4JF4?
,F4JF4?
' '
M N
+
+
+
+

+
+
+
+
E
r
M N
d
MN
= MN>0
MN
d
MN
= -MN <0
+
+
+
+
+
+
+
+
E
r
N
M
H
d
MN
= MH > 0

K==
K==
6=
6=
L
L
:
:
MN
MN
:
:
∞
∞
M-8
M-8
:
:


A
A
M
M
∞
∞
là công của điện trường trong sự
là công của điện trường trong sự
dịch chuyển của điện tích q từ điểm M
dịch chuyển của điện tích q từ điểm M

đến vô cực.
đến vô cực.


8
8
:
:
M
M
O6=.
O6=.
PP=Q
PP=Q
:;
:;


F4:;GER
F4:;GER
!S2",
!S2",
P&' F,
P&' F,
P)-T:=;
P)-T:=;
MN
MN M N
A
U V V

q
= − =
q
k
r
ε
67Q
67Q




83 .
83 .
NM-7'NM-Q
NM-7'NM-Q


QM7'
QM7'
UI)"2 F"
UI)"2 F"
,G
,G
' '
MN
U
E
M N
=

MN
U
E
d
=
A
U
q
=
2 2
2 1
1 1
2 2
mv mv qU− =
V
V
.VF4N/V/+G4W
.VF4N/V/+G4W
4"G+N+MK4/V+M
4"G+N+MK4/V+M
*4X44WP
*4X44WP
8Y1WP
8Y1WP
$N+/$TN
$N+/$TN


+W
+W

$7MZBBB894[).
$7MZBBB894[).
Q
Q
N+
N+
/Q
/Q
+V
+V
/Q
/Q
NV
NV


O+",P!4W
O+",P!4W
YY5Y6' FTN=V\
YY5Y6' FTN=V\
V]^[_`+ab%.+c;d+aN
V]^[_`+ab%.+c;d+aN
e+^f;^fQ^f;[g
e+^f;^fQ^f;[g
A
B
C
E
r
F

r
V%.
V%.
[4NV+"GNE
[4NV+"GNE
RP/
RP/
α
α
MNV+M
MNV+M
hB
hB
B
B
/
/
VN
VN
↑↑
↑↑
V=V+Mh4/Q
V=V+Mh4/Q
V+
V+
M
M
%B8
%B8
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