. R Q +0. , , . (. 128). r, . r>R, Q, , , (81.2), 4pr2 E = Q/e 0, . r>R r , . E r . 129. r'<R, , (E =0).
. R Q r (r = dQ/dV , ). (..3), , , (. (82.3)). . r'<R Q' =4/3pr'3r. , (81.2), 4pr'2 E = Q' /e0=4/3pr3r/e0. , r=Q/(4/3pR3), . , (82.3), r'.
. .
. + s (s=dQ/dS, ). . , , . (cosa=0), , ( E n ), .. 2ES. , , sS. (81.2), 2ES = sS/e 0, E=s/(2ee0). (82.1). (82.1) , , . . , , .
(. 127). +s -s. , . , . ( ), E =0. E = E ++ E - (E + E- (82.1)), E =s/e0. (82.2). , (82.2), , , .
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25.26. . .
: . q , , , (. 13.16).
dx . . : . , , .
.
1. : E=σ/(2ε0), σ . , x1 2 , ( Ex = -∂φ/∂x)
2. : =σ/ε0, σ . , d ( Ex = -∂φ/∂x),
(1)
3. R Q (r>R) : (4πε0)-1(Q/r2) , r1 r2 (r1>R, r2>R, r2>r1),
(2)
r1=r r2=∞, , (2),
4. R Q (r>R) , , E = (4πε0)-1(Q/r2), , r1 r2 (r1>R, r2>R, r2>r1), (2). , r' (r'<R), (82.4): E = (4πε0)-1(Qr'/r3) , , r1' r2' (r1'<R, r1'<R, r2'>r1'),
5. R, τ, (r>R) : E = (2πε0)-1(τ/r) , , r1 r2 (r1>R, r2>R, r2>r1),
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27. . . . . .
. Ad = d1-d2 (. 110), : , d1 d2 .
, . , , . , ' .
180 , , . q , q . , . , , , . . , (.111).
.
, , . .
- , . ..
, : .
. : q 1 2 q0, , , . F dl ,
q0 1 2
(1)
, 1 2 . , , , . (1) , , L, , .. (2). , , + , dl Edl = E1dl, E1=Ecosα . (2) (3). .
28.29 . . .
, (, , , ..) , . , . , , . , , . , . .
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, , ,
, .
, ,