กกก 1 (2104-2102)

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2.1 "##$ (Electric Cell) "##$ .[3 6ก2$ # )#+1.W)#+ X1(='8"##$ก,(%/#]กX, (Electrode) 2 %/ ;0#]กX#&$%#=!X1(0+6(."##$ &+8"##$1.,(%ก %&& (Battery) [b W&( 0++\#+ก42$8"##$1. ,+%,'7 2.2

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7 2.3 "##$%)!;<

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'"##$,+; /#8กก,cก##ก+8+;#]กX, ./#'(ก,ก3กก88+;#]กX,,],] %#.! 8+;#]กX,[7ก0#., %&& ก]..['(,( "##$,;.! h"##$<.=7. (Primary Cell)i %&& ,;..[0+,6 (Charge) '.,(%#+.! ก! "##$%%( (Dry Cell) )## '(8('W%%( +."##$ .[0+,6'. (Recharge) ,(! กcก='"##$.0'(ก,ก3กก88+;#]กX, .! "##$[7ก'(., .[0+,6'.ก%#ก%=ก ก "##$6&=7. (Secondary Cell) %#+.! กก "##$%mก (Wet Cell) )## '(.[W8#

2.2 ก&"##$ ! ก"##$%&#"##$ .%,+1 "##$ W[b '\.%,+1 1.5 X#&$&"##$!&ก( %&& .8&.(&#, '(ก].8, 6 X#&$ 12 X#&$%# 24 X#&$ W&( %&[(&(ก'(%,+ %&ก&ก .7&(0"##$.&)! '(,(%,+&. &(ก X,ก&"##$.[%ก,(,+; 1) ก&"##$%6ก. - ก&"##$%.%,+ - ก&"##$%+ก#(%,+ 2) ก&"##$%8 - ก&%8.1,11.&(='"##$ - ก&%8 1,11.&(='"##$ 3) ก&"##$%/. - ก&"##$%6ก.-8 -ก&"##$%8- 6ก.

2.3 ก&"##$%6ก. (Series Cell Connection) ก&"##$%6ก. 1!ก0"##$.&ก+ !&+,+ก+ 2.3.1 ก ก

'ก&"##$%6ก..%,+ 'ก&%;8+;8"##$.*,ก+ %#&W%[ก+X,ก08+;#8"##$ 1 &ก+8+;ก8"##$"##$ 2 %#8+;ก8"##$ 3 &ก+8+;#8"##$ 2 %#&,+;! p

7 2.4 ก&"##$%.%,+ .1,1.&(='

,( n321ABT E ... E E E E E ++++== (2.1)

7 2.5 ก&"##$%.%,+ %#1,11.&(='

ก7 2.5 ,( n321ABT E ... E E E E E ++++== %# n321ABT r ... r r r r r ++++== (2.2) 2.1 "##$0 3 "##$ %&#"##$.1%,+ 1.5 X#&$ '%&#"##$.1. &(=' 0.1 X$. [(0.&6ก.%.%,+ .%,+. %#1.&(='.

E1 E2 E3

ET

7 2.6

7 2.7

!" %,+. 321T E E E E ++=

1.5 1.5 1.5 ++= V 4.5 = 1.&(='. r r r r 321T ++=

0.1 0.1 0.1 ++= Ω= 0.3 2.3.2 ก ก#ก$

'ก&"##$%6ก.+ก#(%,+;0'(%,+#,# %&1.&(='. (rT) .1ก+/#.81.&(='8%&#"##$.ก+

ET

7 2.7 %,ก&"##$%6ก.+ก#(%,+

7 2.8 %,+\#+ก42$ก&"##$%+ก#(%,+

ก7 2.8 ,( 21T E - E E = (2.3) ก2 E1 .กก E2 %# 12T E - E E = (2.4) ก2 E2 .กก E1

[(1,1.&(='"##$ ,(11.&(='. 21T r - r r = (2.5) 2.2 "##$."##$&6ก.ก+,+7 1%,+.%#1.&( ='.

.! E1 = E2 = E3 = 5 V %# r1 = r2 = r3 = 2 Ω

7 2.9

!" %,+ ET = E1 + E2 - E3 = 5 + 5 w 5 = 5 V 1.&(='. rT = r1 + r2 + r3 = 2 + 2 + 2

= 6 Ω

2.4 ก&"##$%8 (Parallel Cell Connection) 'ก&"##$%8+; "##$ 0.'(&8&(.8,%,+ก+ ก&"##$%8 .[3 ก0"##$&+;%& 2 "##$83;.&8ก+!&1.ก+ X,&'#+ก42 8+;.!ก+&.ก+W6,, %#8+; #!ก]0.&.W6,,ก+ ,+%,'7 2.10 ก&"##$%8./#'(,(ก% #') ..ก83; )"##$%&#"##$ &%8ก%ก.

ET

7 2.10 ก&##$%8

2.4.1 ก &'())$!*+

7 2.11

ก7 2.11 ,( E1 = E2 = V (2.6)

R

V

R

E

R

E I 21

T === (2.7)

n

I I I T

21 == (2.8)

.! n 1!0"##$ 0.&8ก+ 21T I I I += (2.9) 2.4.2 ก &! ())$!*+

7 2.12

ก7 2.12 ,( "##$ E1 .1.&(='1! r1 %#"##$ E2 .1.&(='1! r2 [(1.&(='8%&#"##$.11.&(ก+ ..[11.&(='"##$. (rT) ,++; .! r1 = r2 ,(

21T r

1

r

1

r

1+= (2.10)

! 21

21T r r

r r r

+

×= (2.11)

! n

r

n

r r 21

T == (2.12)

.! n 1!0"##$ &8ก+ RT = rT + R (2.13)

,( T

2

T

1T R

E

R

E I == (2.14)

.RI V T= (2.15)

1

11 r

V - E I = (2.16)

2

22 r

V - E I = (2.17)

2.3 "##$.%,+ 9 V 1.&(='8%&#"##$.1"##$# 2 Ω 0. &8ก+,+7

7 2.13

!"

21

21T r r

r r r

+

×=

2 2

2 2

+

×=

= 1 Ω RT = rT + R = 1 + 12

= 13 Ω

T

2

T

1T R

E

R

E I ==

13

9 =

= 0.69 A

.RI V T= = 0.69 × 12 = 8.31 V

1

11 r

V - E I =

2

8.31 - 9 =

= 0.345 A

2

22 r

V - E I =

2

8.31 - 9 =

= 0.345 A

! n

I I T

1 =

2

0.69 =

= 0.345 A

n

I I T

2 =

2

0.69 =

= 0.345 A

2.5 ก&"##$%/. (Combination Cell Connection) ก&"##$%/. 1!ก0"##$.&'#+ก426ก.%#8.ก+' .[&,( 2 5 1!

2.5.1 ก ก-& 1!ก0"##$#p "##$.&6ก.ก+Wก#6.ก ก+;%#(0ก#6."##$%&#ก#6..&8ก+ก ,+7 2.14

7 2.14

ก7 2.14 ,( ET1 = E1 + E2 %# ET2 = E3 + E4

R r

V I

TT

+=

.! 21T1 r r r += 43T2 r r r +=

T2T1

T2T1T r r

r r r

+

×=

2

I I T

1 =

2

I I T

2 =

%# IT = I1 + I2 2.4 ก7 2.14 1 I1, I2, IT %# V

.! r1 = r2 = r3 = r4 = 1 Ω %# E1 = E2 = 3 V ,E3 = 4 V ,E4 = 2 V

%# R = 5 Ω !" ET1 = E1 + E2

= 3 + 3 = 6 V ET2 = E3 + E4 = 4 + 2 = 6 V ET = ET1 = ET2 = V = 6 V rT1 = r1 + r2 = 1 + 1

= 2 Ω rT2 = r3 + r4 = 1 + 1

= 2 Ω

T2T1

T2T1T r r

r r r

+

×=

4 4

4 4

+

×=

8

16 =

= 2 Ω

R r

E I

T

TT

+=

5 2

6

+=

7

6 =

= 0.857 A V = IT.R

= 0.857 × 5 = 4.285 V

T1

T11 r

V - E I =

4

4.285 - 6 =

4

1.715 =

= 0.429 A

T2

T22 r

V - E I =

4

4.285 - 6 =

4

1.715 =

= 0.429 A 2.5.2 ก &-ก 1!ก0"##$.&8ก+กWก#6. %#(30ก#6.8"##$ &8ก+.&6ก.ก+ก ,+7 2.15 .! %,+%#1.&(='8%&#"##$.1ก+

I T

E T1

E T2

r 1 r 2

r 3r 4

E3

E1 E2

E4

I 1

I 3

I 2

I 4

R V

7 2.15

ก7 2.15 ,( E1 = E2 E3 = E4 '( ET = E1 + E3 ! ET = E2 + E4

21

21T1 r r

r r r

+

×=

43

43T2 r r

r r r

+

×=

r r r T2T1T +=

R r R TT +=

T

TT R

E I =

21 I I += 43 I I +=

I1 = I2 = I3 = I4 = 2

IT

ET1 = E1 w I1.r1 ! E2 w I2.r2 ET2 = E3 w I3.r3 ! E4 w I4.r4 2.5 ก'7 2.15 1 IT, I1, I2, I3, I4, ET1, ET2 %# V

.! r1 = r2 = r3 = r4 = 2 Ω %# E1 = E2 = E3 = E4 = 6 V

R = 6 Ω !" ก E1 = E2 = 6 V E2 = E2 = 6 V '( ET = E1 + E2 = 6 + 6 = 12 V

21

21T1 r r

r r r

+

×=

2 2

2 2

+

×=

= 1 Ω

43

43T2 r r

r r r

+

×=

2 2

2 2

+

×=

= 1 Ω

r r r T2T1T += = 1 + 1

= 2 Ω

R r R TT += = 2 + 6

= 8 Ω

T

TT R

E I =

8

12 =

= 1.5 A

I1 = I2 = I3 = I4 = 2

IT

2

1.5 =

= 0.75 A ET1 = E1 w I1.r1

= 6 w (0.75 × 2) = 4.5 V ET2 = E3 w I3.r3

= 6 w (0.75 × 2) = 4.5 V V = IT.RT

= 1.5 × 8 = 12 V