1. 2 10

2. 0 - + - + - + = 0 = 0

3. http://www.youtube.com/watch?v=N8lB6LuqOUo

4. : ()

5.

6. = 0 1, < 0 , 0 =

7. 81 2,1 2,5 2 7

8. 1. k q1 q2 F= r 22. , kQ E= r 2

9. 3. kQ 2 , _ r R E = r 0, _ r < R 4. E= Q 2 0 S5. Q E= 0 S

10. + E - A = Fs cos A = Eqs cos F A = Eq(d1 d2) s 2. 1. 3. 0

11. - : Wp = Eqd : = Wp q = Ed [] = 1

12. : A = Eqd1 Eqd2 = W1 W2 A = - Wp : A = q( 1 2) 1 2 = U

13. - : mv12 mv2 2 + Eqd1 = + Eqd 2 2 2 mv12 mv22 + q1 = + q 2 2 2

14. d U = Ed

15. A = q( 1 2) = 90 A = 0s 1 1 = 2 2

16. - kQr kQ = E r = 2 = r r- kQq W p = q = r- kQq 1 1 A = p = W r1 r2

17. 2. 3. q C=

18. [C] = 1 () 1 1 = 1 6 1 = 10 9 1 = 10 12 1 = 10

19. ( . Condensator , ) .

20. :1. C ~ q2. 1 C~ U q = U

21. 1. C ~ S ( )3.C ~ ( ) 14.C ~ ( ) d 0 S C= d

22. .. Wp =Eqd, Wp = Eqd/2 qU Ed = U W p = 2 q q2 U = Wp = C 2C CU 2 q = CU W p = 2

23. 1. , q = const: 2 . , , , ? 0 S = d q q = U = U C U E= d q2 Wp = 2C

24. 2. , U = const: , , ? 0 S = d q = q = CU U U E= d CU 2 Wp = 2

25. 1. q1 = q2 U = U1 + U2 q q q 1 1 1 = + = + C C1 C2 C C1 C2

26. 2. U = U1 = U2 q = q1 + q2 CU = C1U + C2U C = C1 + C2