Bab 6 Induksi Elektromagnetik

memformulasikan konsep induksi Faraday dan arus bolak-balik, keterkaitannya, serta aplikasinya.

Setelah mempelajari bab ini, Anda harus mampu:

menerapkan konsep kelistrikan dan kemagnetan dalam berbagai penyelesaian masalah dan produk teknologi.

Hasil yang harus Anda capai:

Induksi

Elektromagnetik

A. Gejala Induksi

Elektromagnetik

B. Aplikasi Induksi

Elektromagnetik

Faraday

C. Arus dan Tegangan

Listrik Bolak-balik

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?<58;1F1C25A1ADB<9BCA9; 5:1<19>9C5<18491=1C9?<58*.$-%./%* "-./"!@141-18D;18>41218F1@5AD2181>=541>=17>5C 41@1C=5>9=2D<;1>1ADB<9BCA9;

5:1<19>949=1>611C;1>D>CD;=5>781B9<;1><9BCA9;G1>7497D>1;1> D>CD;25A21719;5@5A<D1>,5217193?>C?8B5@5AC9C1=@1;@14171=21A B52D1875>5A1C?AA1;B1B1497D>1;1>B521719BD=25A<9BCA9; 5>5A1C?A 9>9 =5=1>611C;1> 75:1<1 9>4D;B9 5<5;CA?=17>5C9; @1;18 9>4D;B9 5<5;CA?=17>5C9;9CD41;18@5=1>611C1><19>41A99>4D;B95<5;CA?=17 >5C9; B5<19> 75>5A1C?A 5B1A1>25B1A1> 1@1 B1:1 G1>7 C5A<921C 41<1= 9>4D;B95<5;CA?=17>5C9;#1F121>1C1B@5AC1>G11>@5AC1>G11>C5AB52DC 41@1C>41C5=D;1>41<1=2129>9(<58;1A5>19CD@5<1:1A9<182129>9 45>71>219;

Generator listrik mampu mengubah energi kinetik menjadi energi listrik melalui proses induksi elektromagnetik.

Bab

6

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Tes Kompetensi Awal

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A. Gejala Induksi Elektromagnetik

1. Pengertian Induksi Elektromagnetik

*. $-%./%* "-./"!C5<1825A81B9<=5=2D;C9;1>218F11ADB <9BCA9;41@1C=5>9=2D<;1>=541>=17>5C9;D125<1BC18D>;5=D491> B5C5<18@5>5=D1>(5ABC54B5?A1>718<969B9;125A>1=1% $"(-!2

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)-

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Gambar 6.1 Induksi elektromagnetik (a) ketika magnet diam, jarum galvanometer juga diam, (b) ketika magnet dimasukkan ke dalam kumparan, jarum galvanometer bergerak ke kanan, dan (c) ketika magnet dikeluarkan dari dalam kumparan, jarum galvanometer bergerak ke kiri.

1

2

3

Aktivitas Fisika 6.1

Induksi Elektromagnetik Tujuan Percobaan

Mengamati arus induksi Alat-Alat Percobaan 1. Kumparan 2. Galvanometer 3. Magnet batang

Langkah-Langkah Percobaan

1. Susunlah peralatan seperti gambar berikut.

kumparan magnet

2. Hukum Faraday

7< 9>4D;B9 4981B9<;1> 41A9 @A?B5B 9>4D;B9 5<5;CA?=17>5C9; 7< 9>4D;B9C9=2D<:9;1141@5AD2181>6<D;B=541>=17>5C4941<1=

;D=@1A1> 7<9>4D;B99>9<18G1>7=5>G5212;1>=5>71<9A>G11ADB<9BCA9; 9>4D;B9@141BD1CDA1>7;191>C5ACDCD@

5B1A>G177<9>4D;B925A71>CD>7;5@14161;C?A61;C?AB52171925A9;DC

1 $.*+."( &.%,'('!(-&'%.'*+(,5=1;9>25B1A

<1:D@5AD2181>>G1B5=1;9>25B1A@D<177<G1>74981B9<;1>

2 .'&"&#&#-(%.'*+(,5=1;9>21>G1;:D=<18<9<9C1>;D=@1A1> B5=1;9>25B1A@D<177<G1>74981B9<;1>

5A41B1A;1>81B9<5;B@5A9=5>G1>749<1;D;1>>G1-!2=5>GDBD> !D;D=1A141G!D;D=9>9G1>7=5>G1C1;1>218F1!2!+%&#,-+#% #(.%,#,(#(!(!(&$.*+."( &.%,'('!(-2(!-+$## &'%.'*+()5A>G1C11>!D;D=1A141G9>941@1C49>G1C1;1>41<1= 25>CD;@5AB1=11>B52171925A9;DC

J

$5C5A1>71>

77<9>4D;B9/

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@5AD2181>6<D;B=17>5C9;02

:D=<18<9<9C1>

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@5AB1=11>25A9;DC

3?B

J

$5C5A1>71>

;D1C=541>=17>5C9;02 = <D1B2941>7;D=@1A1>=

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;D=@1A1>

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1 @5AD2181>;D1C=541>=17>5C9;

2 @5AD2181><D1B2941>7;D=@1A1>G1>749C5=2DB?<58=541>=17>5C9; 2. Siapkan magnet batang, kemudian dekatkan pada kumparan, dan diamkan.

Catat hasil pengamatan Anda.

3. Gerakkan magnet mendekati kumparan atau masukkan ke dalam kumparan. Amati jarum galvanometer dan catat hasil pengamatannya.

4. Diamkan magnet batang di dalam kumparan. Amati jarum galvanometer dan catat hasil pengamatannya.

5. Gerakkan magnet batang dengan arah menjauhi kumparan atau keluar kumparan, amati jarum galvanometer, dan catat hasil pengamatannya. 6. Balikkan polaritas magnet batang, lakukan lagi percobaan langkah 2 dan

langkah 5. Catat hasil pengamatannya. 7. Tulis kesimpulan Anda tentang kegiatan ini.

Gambar 6.2

Garis-garis gaya magnetik yang membentuk sudut terhadap garis normal.

Tokoh

Michael Faraday (1791–1867)

Michael Faraday adalah seorang ahli Fisika, ahli Kimia, dan ahli Filsafat berkebangsaan Inggris, tepatnya lahir di Newington Butts, Surey, pada tahun 1971. Ia bersama-sama dengan Joseph Henry menemukan

fenomena induksi elektromagnetik. Penemuan ini merupakan kebalikan dari penemuan Oersted, yaitu dari medan listrik dapat menghasilkan arus listrik.

Sumber:www.allbiographies.com

B

A

garis normal

Tantangan

untuk Anda

Bagaimana pengaruh perubahan lilitan terhadap ggl induksi?

,52D18=17>5C4975A1;;1>=5>:1D89;D=@1A1>G1>7C5A49A91C1B<9<9C1>1<1= F1;CDB6<D;B=17>5C9;G1>7=5>5=2DB;D=@1A1>25A;DA1>741A9KJ₀₂

=5>:149KJ_{025A1@177<G1>7499>4D;B9;1>@141D:D>7D:D>7;D=@1A1>}

1

9;5C18D9

<9<9C1>

B

KJ02JKJ02

JKJ₀₂

02

/

B

#14977<G1>7499>4D;B9;1>141<18/

Contoh

6.1

3. Ggl Induksi karena Perubahan Luas Bidang Kumparan

,5BD1945>71>!D;D=1A141GB5C91@;1<9BD1CD21C1>7;?>4D;C?A 25A75A1; 41<1= =541> =17>5C9; 89>771 =5=?C?>7 71A9B71A9B 71G1 =17>5C9; 1;1> C9=2D< 77< 9>4D;B9 7< 9>4D;B9 41@1C C5A:149 1;921C @5AD2181><D1B2941>7;D=@1A1>G1>749C5=2DB?<58=541>=17>5C9; )5A81C9;1>)-&541>=17>5C8?=?75>45>71>A1@1C71A9B 71G141>C571;<DADB=1BD;2941>7;5AC1B#9;1@5>781>C1A)*4975A1; ;1>;5;1>1>45>71>;535@1C1>/B5:1D811;1>C5A:149@5AD2181>71A9B 71G1G1>749<9>7;D@9?<5821C1>7;?>4D;C?A)*45>71>A1>7;191>;1F1C .)5AD2181><D1B@5AB1CD1>F1;CD1;921C@5A75B5A1>21C1>7;?>4D;C?A )*=5=5>D89@5AB1=11>25A9;DC

1 1 _/

- - -

5>71>45=9;91>77<9>4D;B9=5=5>D89@5AB1=11>25A9;DC

/

- -

J

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A18 1ADB 9>4D;B9 G1>7 49@5A<981C;1> @141)- 41@1C 49C5>CD;1>45>71>=5>5A1@;1>!D;D=%5>HG1>7=5>G1C1;1>218F1 :9;11A189>4D;B9=17>5C=5>D:D;541<1=2941>7;5AC1B41>1A18/

Gambar 6.3 Penghantar PQ digerakkan dengan kecepatan vdi dalam medan magnet homogen B.

B

R

P

Q

v

x

I

Gambar 6.4 Gerak elektron dalam batang konduktor bergerak di atas medan magnet.

v F

;5;1>1>=D1C1>>571C96@14121C1>7;?>4D;C?A)*1;1>=5>41@1C 71G1 ;5 21F18 A18 1ADB <9BCA9; B5BD19 45>71> 1A18 =D1C1> @?B9C96 B589>7711A181ADB9>4D;B941<1=21C1>7;?>4D;C?A141<1841A9*;5) (<58;1A5>11A181ADB9>4D;B941<1=21C1>7;?>4D;C?A41A9*;5) B541>7;1>1A189>4D;B9=17>5C9;;541<1=2941>7;5AC1B1;1>C9=2D< 71G1=17>5C9;G1>71A18>G1;5;9A9>4141@1C=5=2D;C9;1>>G1 =5>77D>1;1>;19418C1>71>;1>1>5B1A>G171G1=17>5C9;C5AB52DC =5=5>D89@5AB1=11>

J

>41@5A81C9;1>;5=21<9)- 1<1=;1F1C.=5>71<9A 1ADB<9BCA9;1;921C141>G12541@?C5>B91<491>C1A1C9C9;)41> *5B1A>G12541@?C5>B91<C5AB52DCB1=145>71>25B1A>G177<9>4D;B9 @14121C1>7;?>4D;C?A

5A41B1A;1>!D;D=(8=25B1A>G1;D1C1ADB<9BCA9;G1>7=5>71<9A @141;1F1C.141<18B52171925A9;DC

/

J &5>DADC!D;D=$5;5;1<1>>5A795>5A79G1>7497D>1;1>D>CD; =5=9>418;1> =D1C1> 49 41<1= 21C1>7 ;?>4D;C?A )* B1=1 45>71> 5>5A79G1>7497D>1;1>D>CD;=5=9>418;1>=D1C1>@141;1F1C.(<58 ;1A5>19CD;D1C1ADBG1>7=5>71<9A41<1=;1F1C.B1=145>71>;D1C 1ADB9>4D;B9G1>7=5>71<9A@14121C1>7;?>4D;C?A)*5>71>45=9;91>

"-.)* 3 41@1C 49BD2BC9CDB9;1> ;5 41<1="-.)* 3 B589>77149@5A?<58@5AB1=11>21ADB52171925A9;DC

/

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J $5C5A1>71>

71G1%?A5>CH' / ;535@1C1>= B

;D1C=541>=17>5C02 =

@1>:1>7@5>781>C1A=

81=21C1>

Para teknisi ini sedang memasang generator pada instalasi pembangkit listrik di Meksiko. Bagian yang terlihat di sini adalah stator, yang tidak bergerak. Selanjutnya, ke dalam stator itu dimasukkan rotor. Rotor merupakan sebuah elektromagnetik kuat yang dapat berputar dengan kecepatan tinggi. Akibat perputaran rotor, terjadi perubahan medan magnetik dan membangkitkan arus listrik pada kumparan di dalam stator.

The pisture have shown the technician placing generator on electrical instalation in Mexico. You can see a part, called stator. The rotor is put inside it. Rotor is a strong electromagnetic device that can spin with cause the velocity. That spin is what cause the change of magnetic field and generate electrical element on coil inside stator.

Sumber: The Oxford Children’s Book of Science, 1995

Informasi

untuk Anda

Information for You

Contoh

6.2

$1F1C@5>781>C1A)*@1>:1>7>G13=41>=1BB1>G1741@1C25A75A1;E5AC9;1< 2521B;521F18@141;1F1CA1>7;191>9B5;9C1A>G1C5A41@1C=541>=17>5CB525B1A -45>71>1A18;5<D1A2941>7;5AC1BB5@5AC9C1=@1;@14171=21A

Q

P

B

F

v

w = mg

0,25 R

Tantangan

untuk Anda

Sebuah penghantar berbentuk U terletak di dalam daerah berinduksi magnetik homogen B = 4 × 10–3 _T

berarah menembus bidang kertas. Penghantar PQ sepanjang 40 cm menempel pada penghantar U dan digerakkan ke kanan dengan kecepatan tetap v = 10 m/s. Hitung ggl induksi antara ujung-ujung PQ.

arah telapak tangan

arah jari lain arah ibu jari

F

B I

-5>CD;1>

1 1A181ADB41<1=;1F1C@5>781>C1A)*

2 ;535@1C1>;?>BC1>;1F1C@5>781>C1A

1

1 1G125A1C@5>781>C1A)*B525B1A'!=5>G5212;1>@5>781>C1A)*25A75A1; 45>71>;535@1C1>/;521F18 5A1;@5>781>C1A)*G1>7=5=?C?>7C571; <DADB=541>=17>5C=5>9=2D<;1>71G1%?A5>CHG1>71A18>G1;51C1B $535@1C1>;?>BC1>@5>781>C1A)*C5A31@19;5C9;125B1A71G1%?A5>CHB1=1 45>71>25B1A71G125A1C@5>781>C1A)*,5BD1945>71>!D;D=%5>H218F1 1A181ADB41@1C49C5>CD;1>45>71>1CDA1>;19418C1>71>;1>1>B5@5AC9@141 71=21AA189>4D;B9=17>5C9;;5<D1A2941>71A1871G1%?A5>CH;51C1B41> 1A181ADB#@141@5>781>C1A;5;9A9G19CD41A9*;5)

2 $535@1C1>;?>BC1>C5A31@19;5C9;171G1%?A5>CHB1=145>71>71G125A1C @5>781>C1A

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/

B541>7;1>71G1'!B589>771

/

'!

'! /

&

/

;7 = B 02 = =

= B

#149;535@1C1>;?>BC1>;1F1C141<18= B

4. Induktansi Diri

#9;1B52D18;D=@1A1>491<9A91ADB<9BCA9;G1>725B1A>G125AD218 D218C5A8141@F1;CD1;1>C9=2D<6<D;B=17>5C9;'G1>725B1A>G1

:D7125AD218C5A8141@F1;CD)5AD2181>6<D;B=17>5C9;B521>49>745>71> ;D1C1ADB,531A1=1C5=1C9B49CD<9BB52171925A9;DC

' 1C1D' J1

45>71>=5AD@1;1>BD1CD;?>BC1>C1G1>749B52DC45>71>9>4D;C1>B9 49A9 ;D=@1A1> C5AB52DC ">4D;C1>B9 49A9 C571; <DADB C5A8141@ 25>CD; 75?=5CA9;;D=@1A1>>G1,1CD1>9>4D;C1>B991<1885>AG!5>CD; D=D= 9>49;1C?A 25AD@1 B?<5>?941 B531A1 <1>7BD>7 9>4D;C1>B9 49A9 B?<5>?9419>941@1C4989CD>7B5@5AC925A9;DC9>9

'

J2

Induktor adalah sebuah elektromagnet, yaitu sebuah kumparan kawat dengan atau tanpa inti magnetik yang menghasilkan magnetisme jika arus mengalir melewatinya.

Inductor is an electromagnet, made of wire coil with or without magnetic core which can produce magnetism when electric current through.

Sumber:Jendela Iptek, 1997

Informasi

untuk Anda

Sumber:www.linearmagnetics.com

(<58;1A5>16<D;B=17>5C9;D>CD;<9<9C1>@141B?<5>?941141<18

'

(

( =1;19>4D;C1>B949A9B?<5>?941141<18

B52171925A9;DC

( J

"-.)* 325A<1;D:D71D>CD;9>4D;C1>B949A9@141@DB1C C?A?941;1A5>125B1A9>4D;B9=17>5C491>C1A1;54D1>G1B1=1G19CD B525B1A(

#9;1@5>1=@1>7B?<5>?9411C1DC?A?941499B9?<582181>G1>7=5=9<9;9 @5A=5129<9C1BA5<1C96+49=1>1@5A=5129<9C1B2181>141<18

+ J ">4D;C1>B949A9B?<5>?94141>C?A?94145>71>2181>C5AB52DC141<18 +

(

J

$5C5A1>71>

9>4D;C1>B949A9B?<5>?9411C1DC?A?94145>71>9>C92181>! 9>4D;C1>B949A9B?<5>?9411C1DC?A?941C1>@19>C9!

Gambar 6.5

Sebuah rangkaian tertutup (a) saklar s

ditutup, lampu menyala dan (b) saklar s

dibuka, lampu masih menyala beberapa saat kemudian padam.

1 S S I L L P P 2

Contoh

6.3

-?A?94145>71><D1B@5>1=@1>73=_{41>@1>:1>7>G13==5=9<9;9<9<9C1>}

-5>CD;1><189>4D;C1>B949A9C?A?941C5AB52DC

1

9;5C18D9

3=_KJ₌

3==

KJ02 =

B589>77149@5A?<58

02 = =

=

KJ_!!

#1499>4D;C1>B949A9C?A?941141<18!

,D1CDA1>7;191>G1>7C5A49A91C1BB52D18;D=@1A1>9>4D;C?A B52D18<1=@D)41>BD=25AC571>71>

G1>749<5>7;1@945>71>B52D18

B1;<1AC1=@1;@141)-$5C9;1B1;<1A498D2D>7;1><1=@D C941;B575A1=5>G1<1=1;B9=D=C5C1@9141:541F1;CDB5B11C)141B11C 1ADB49@DCDB;1>@141B1;<1A@5>78D2D>7<1=@DC941;B575A1@141= C5C1@9141:541F1;CDB5B11C)5A81C9;1>)-)5A9BC9F19>9 =5>D>:D;;1> C9=2D<>G1 1ADB 9>4D;B9 G1>7 49B5212;1> ?<58 141>G1 @5AD2181>6<D;B=17>5C9;@1419>4D;C?A

)5AD2181> 1ADB @141 B52D18 ;D=@1A1> 41@1C =5>9=2D<;1> 77< 9>4D;B9G1>725B1A>G125A21>49>7<DADB45>71>35@1C>G1@5AD2181>;D1C 1ADB>G1,531A1=1C5=1C9B@5A>G1C11>G1>749;5=D;1;1>@5AC1=1;1<9 ?<58+.",$"*-29>949CD<9B;1>B52171925A9;DC

_J

Pembahasan Soal

Kuat arus listrik dalam suatu rangkaian tiba-tiba turun dari 10 A menjadi 2 A dalam waktu 0,1 s. Selama peristiwa ini terjadi, timbul ggl induksi sebesar 32 V dalam rangkaian. Induktansi rangkaian adalah ....

a. 0,32 H b. 0,40 H c. 2,5 H d. 32 H e. 40 H

UMPTN 1993 Pembahasan:

Diketahui:

I = 10 A – 2 A = 8 A

ind = 32 V

ind dI L d

32 V = 3,2 V 8 A

s

L = 3,2 8

s

V A = 0,4 H

Gambar 6.6 Sebuah kawat induktor yang dialiri arus listrik.

I

a b

-1>41>571C96=5AD@1;1>@5>G5BD191>45>71>!D;D=%5>H#9;1 <1:D@5AD2181>;D1C1ADB_-

;?>BC1>=1;1"-.)*341@1C

49CD<9B;1>B52171925A9;DC

-

J

$5C5A1>71>

;D1C1ADB<9BCA9;@141;51411>1F1< ;D1C1ADB<9BCA9;@141;51411>1;89A

-J-B5<1>7F1;CD@5AD2181>;D1C1ADB<9BCA9;B

Contoh

6.4

,52D18;D=@1A1>45>71>9>4D;C1>B949A9!491<9A91ADBB5217196D>7B9F1;CD

J-_{41<1=1=@5A541>-41<1=B5;?>-5>CD;1>77<9>4D;B949A9G1>7C5A:149}

B11C-B

1

9;5C18D9

!

J-

5>71>=5>77D>1;1>"-.)*3 49@5A?<58

-

J!J-

JJ /

#14977<9>4D;B949A9@141B11C-141<18/

5. Energi yang Tersimpan dalam Induktor

">4D;C?A=1=@D=5>G9=@1>5>5A79>5A79C5AB52DCC5AB9=@1>41<1= 25>CD;=541>=17>5C)5A81C9;1>)-#9;1B52D189>4D;C?A 491<9A91ADB<9BCA9;G1>7B5<1<D25AD218C5A8141@F1;CD25B1A>G1C571>71> 1>C1A1C9C9;41>141<18

_- J

B589>77125B1A>G141G1G1>74925A9;1>@1419>4D;C?A141<18

_-

J

>5A79 G1>7 4925A9;1> @141 9>4D;C?A 49@5A?<58 45>71> =5>7 9>C57A1B9;1>41G1@1419>4D;C?AB589>77149@5A?<58@5AB1=11>

J

6. Rapat Energi dalam Bentuk Medan Magnetik

-5<18 49;5C18D9 25B1A>G1 9>4D;B9 =17>5C9; 49 @DB1C B?<5>?941 =5=5>D89@5AB1=11>25A9;DC

(1C1D

(

41@D>9>4D;C1>B949A9@141B?<5>?941141<18( #9;1>9<19 41>>9<199>4D;C1>B9>41BD2BC9CDB9;1>;541<1="-.)*3

1;1>49@5A?<58@5AB1=11>

(

(

_J

5>71>E?<D=5B?<5>?941 C?A?941141<18 #9;1A1@1C5>5A79

1C1D5>5A79@5AB1CD1>E?<D=5;9C14925A9>?C1B925A<1;D8D2D>71>

_J

Contoh

6.5

,52D18B?<5>?941=5=9<9;9:D=<18<9<9C1>B521>G1;2D18@1>:1>741><D1B @5>1=@1>7B?<5>?941141<183=41>3=_!9CD>7<18

1 9>4D;C1>B949A9B?<5>?941

2 5>5A79G1>74981B9<;1>@141B?<5>?941:9;11ADB<9BCA9;G1>7=5>71<9AB525B1A 3 25B1A77<9>4D;B949A9G1>7C5A:149:9;141<1=F1;CDB;D1C1ADB25AD218=5>:149

1

9;5C18D9

<9<9C1>

3=_KJ₌

3=KJ=

1 ">4D;C1>B949A9B?<5>?941141<18

02 = = _!

=

2 >5A79G1>74981B9<;1>@141B11C141<18

_{! #}

3 5B1A %9>4D;B949A9:9;11ADB25AD218=5>:149141<18

_{! /}

B

Tantangan

untuk Anda

Kata Kunci

• gaya gelak listrik (ggl) • induksi elektromagnetik • Hukum Faraday • fluks medan magnetik • Hukum Lenz • gaya Lorentz • ggl induksi diri • kumparan primer • kumparan sekunder • induktansi silang

Gambar 6.8 Perubahan arus pada kumparan 1 akan memengaruhi arus pada kumparan 2.

I

8. Induktansi Silang

)5A81C9;1>)- -1=@1; 4D1 2D18 ;D=@1A1> G19CD ;D=@1A1>@A9=5A)41>;D=@1A1>B5;D>45A,G1>725A45;1C1>$D=@1A1> @A9=5A)498D2D>7;1>45>71>BD=25AC571>71>

41>81=21C1>E1A9125< $D=@1A1>B5;D>45A,498D2D>7;1>45>71>B52D1871<E1>?=5C5A #9;1 @141 ;D=@1A1> @A9=5A C5A:149 @5AD2181> ;D1C 1ADB 45>71> =5>7D218D21881=21C1>1;1>C5A:149@5AD2181>6<D;B=17>5C9;@141 ;D=@1A1> @A9=5A 5>71> 45=9;91> 6<D;B =17>5C9; G1>7 49<9>7;D@9 ;D=@1A1>B5;D>45A@D>1;1>25AD218@D<1)5AD2181>6<D;B=17>5C9; C5AB52DC1;1>=5>9=2D<;1>77<@141;D=@1A1>B5;D>45A

7<G1>7C9=2D<@141;D=@1A1>@A9=5A=1D@D>;D=@1A1>B5;D>45A 49B52DC#(.%-(,#,#&(!1C1D#(.%-(,#-#'&&#%5B1A>G177<9>4D;B9 G1>7C9=2D<@141;D=@1A1>B5;D>45A;1A5>1@5>71AD8@5AD2181>6<D;B =17>5C9;41<1=F1;CD-=5=5>D89@5AB1=11>

-

J

_-

_J

#9;1"-.)*349C9>:1D<5298<1>:DC49@5A?<58

1C1D

-

5>71>=5C?459>C57A1B91;1>49@5A?<58

_J

5>71> =5>77D>1;1> @5>1<1A1> G1>7 B1=1 =1;1 41A9"-.)* 3 1;1> 49@5A?<58

_J

5B1A6<D;B=17>5C9;G1>749C9=2D<;1>?<581ADB<9BCA9;45>71>

:D=<18<9<9C1>141<18

#9;1>9<1949BD2BC9CDB9

;1>;541<1="-.)*3 49@5A?<58@5AB1=11>25A9;DC

J

$5C5A1>71>

;D1C1ADB<9BCA9;;D=@1A1>@A9=5A 9>4D;C1>B9B9<1>7!

:D=<18<9<9C1>;D=@1A1>B5;D>45A :D=<18<9<9C1>;D=@1A1>@A9=5A

6<D;B=17>5C9;G1>749<9>7;D@9?<58;D=@1A1>B5;D>45AG1>749

C9=2D<;1>?<58;D=@1A1>@A9=5A02

Gambar 6.7 Induktor silang antara dua buah kumparan.

R

P S

Contoh

6.6

,52D18B?<5>?941;D=@1A1>=5=9<9;9@1>:1>73=45>71><D1B@5>1=@1>7 KJ_{=41>21>G1;<9<9C1>}

<9<9C1>9B5;9C1A@DB1CB?<5>?941

49<9<9C;1>;D=@1A1>45>71>21>G1;<9<9C1><9<9C1>-5>CD;1>

1 9>4D;C1>B9B9<1>7;54D1;D=@1A1>

2 77<G1>7C9=2D<@141;D=@1A1>:9;1@141;D=@1A1>=5>71<9A1ADBB525B1A G1>725A21<9;1A1841<1=F1;CDB

1

1 5>71>=5>77D>1;1>"-.)* 3 25B1A9>4D;C1>B9B9<1>741@1C 49C5>CD;1>B52171925A9;DC

02 = =

=

KJ_!

2 )141;D=@1A1>D>CD;B5<1>7F1;CD-B;D1C1ADB25A21<9;1A18 B589>771#JJJ5B1A77<9>4D;B9@141;D=@1A1>

41@1C49@5A?<58B52171925A9;DC

2

! _B

/

Tes Kompetensi

Subbab

A

"-&'*($!()0'0(/%$*

#9;1=17>5C@5A=1>5>4975A1;;1>=5=1BD;9;D=@1A1> ;1F1CG1>7C5A@1B1>7B52D181=@5A5=5C5A1<1CD;DA 1ADB:1AD=1=@5A5=5C5A1;1>=5>G9=@1>741A9 ;54D4D;1> B5C9=21>7>G1 5B1A1> 1@1;18 G1>7 =5>G5212;1>C9=2D<>G1@5>G9=@1>71>C5AB52DC @1;18G1>7C5A:149@141:1AD=1=@5A5=5C5A:9;1 1 21C1>7=17>5C491=41<1=;D=@1A1> 2 21C1>7=17>5C4975A1;;1><529835@1C

3 21C1>7=17>5C4975A1;;1>;5<D1A41A9;D=@1A1> <D;B=17>5C9;G1>7=5=?C?>7BD1CD;D=@1A1> 25A;DA1>741A902=5>:1490241<1=F1;CDB #9;1;D=@1A1>C5A49A91C1B<9<9C1>C5>CD;1>77<G1>7 4981B9<;1>

)141B52D189>4D;C?A45>71><9<9C1>=5>71<9A1ADB <9BCA9;G1>725AD218C5A8141@F1;CDG19CD B 1<1=F1;CDG1>7B1=1=5>9=2D<;1>@5AD2181> 6<D;B=17>5CG1>749<9>7;D@9>G1B525B1A02 -5>CD;1>

1 9>4D;B949A9;D=@1A1>

2 77<9>4D;B949D:D>7D:D>7;D=@1A1>

,5@?C?>7;1F1C25A75A1;=5=?C?>7=541>=17>5C9; 8?=?75>G1>725B1A>G1-41>=5=25>CD;BD4DC I#9;1<D1B6<D;BG1>7C5A@?C?>7=_41<1=F1;CD

BC5>CD;1>77<9>4D;B9G1>7C9=2D<

$1F1C)*B5@1>:1>73=4975A1;;1>;5;1>1> 45>71>;535@1C1>= B41>=5=?C?>7C571;<DADB 9>4D;B9=17>5C9;KJ_{-B5@5AC9@14171=21A}

-5>CD;1>25B1A71G1%?A5>CH@141;1F1C)*41>1A18 1ADB>G1

1<1=B52D18;D=@1A1>C5A41@1C@5AD2181>;D1C1ADB B525B1AG1>7=5>9=2D<;1>@5AD2181>6<D;B =17>5C9;02@141;D=@1A1>;54D1G1>7C5A<5C1; 49<D1A;D=@1A1>@5AC1=1-5>CD;1>9>4D;C1>B9B9<1>7 ;54D1;D=@1A1>:9;1;D=@1A1>;54D1=5=9<9;9 <9<9C1>

Q P

R = 0,5

v = 20 m/s

B

sikat karbon

cincin luncur arah putaran

kumparan

B. Aplikasi Induksi Elektromagnetik Faraday

@<9;1B99>4D;B95<5;CA?=17>5C9;1A141G41<1=;5894D@1>B581A9 81A91>C1A1<19>B52171925A9;DC

1. Generator

)5A>18;18>4125A;D>:D>7;5C5=@1C)5=21>7;9C%9BCA9;-5>171 9AG1>714149#1C9<D8DA#1F11A1C9B1>1C5A41@1C1<1C<9BCA9;G1>7 49>1=1;1>!(+-)+ 5>5A1C?A141<181<1CG1>725A6D>7B9=5>7D218 5>5A79 ;9>5C9; =5>:149 5>5A79 <9BCA9; 5>5A1C?A 25;5A:1 25A41B1A;1> @A9>B9@ 9>4D;B9 5<5;CA?=17>5C9; -5A41@1C 4D1 :5>9B 75>5A1C?A G19CD 75>5A1C?A1ADB2?<1;21<9;41>75>5A1C?A1ADBB51A18

a. Generator Arus Bolak-Balik

)-=5>D>:D;;1>B;5=175>5A1C?A1ADB2?<1;21<9;1A1 ;5A:175>5A1C?AC5AB52DC141<18B52171925A9;DC

$D=@1A1>G1>749<5C1;;1>41<1==541>=17>5C9;49@DC1AB589>771 =5>71<1=9@5AD2181>:D=<1871A9B71G1=17>5C9;;921C>G1C5A:149 77<9>4D;B9G1>7=1=@D=5>781B9<;1>1ADB<9BCA9;ADB<9BCA9;G1>7 4981B9<;1>>G125AD@11ADB2?<1;21<9;1C1D &-+(-#(!.++(- ;1A5>1B5C91@;1A2?>1;1>=5>41@1C;1>@?<1A9C1B77<9>4D;B9G1>7 25AD218D218;DCD2@?B9C9641>;DCD2>571C96B531A125A71>C91> .>CD;=5>G1<DA;1>1ADB<9BCA9;G1>749@5A?<58;54D1D:D>7;D=@1A1>

49@1B1>7939>39>G1>7C5A@9B1841>49C5=@5<;1>@141B9;1C;1A2?> G1>7498D2D>7;1>45>71>;125<@5>G1<DA

b. Generator Arus Searah

)14141B1A>G1@A9>B9@;5A:175>5A1C?A1ADBB51A18B1=145>71>@A9>B9@ ;5A:1 75>5A1C?A 1ADB 2?<1;21<9; )5A25411>>G1 @141 75>5A1C?A 1ADB B51A1849@1B1>7%)'.--)+25AD@1B52D1839>39>25<18D>7B9;?=DC1C?A 9>9=5>71CDA171AB5C91@B9;1C;1A2?>B5<1<D=5>41@1C;1>@?<1A9C1B77< 9>4D;B9G1>7C5C1@B9;1C@5AC1=1@?B9C9641>B9;1C<19>>G1>571C96

2. Transformator (Trafo)

+(, )+'-)+141<181<1CG1>725A6D>7B9=5>7D218=5>19;;1>1C1D =5>DAD>;1>C571>71><9BCA9; (<58;1A5>19CDCA1>B6?A=1C?A492179 =5>:1494D1:5>9BG19CDCA1>B6?A=1C?A,-*.*41>CA1>B6?A=1C?A,-*)0(

Gambar 6.9 Skema generator arus bolak-balik

Gambar 6.10 Skema generator arus searah

kumparan

komutator

sikat karbon

-A1>B6?A=1C?AC5A49A91C1B;D=@1A1>@A9=5A;D=@1A1>B5;D>45A41>9>C9 25B9?>C?8CA1>B6?A=1C?A49CD>:D;;1>@141)-

a. Transformator Step-up

-A1>B6?A=1C?A,-*.*25A6D>7B9=5>19;;1>C571>71><9BCA9;171> B545A81>1B52D18CA1>B6?A=1C?A,-*.*49CD>:D;;1>@141)- )141CA1>B6?A=1C?ABC5@D@:D=<18<9<9C1>B5;D>45A<529821>G1;41A9@141 :D=<18<9<9C1>@A9=5A,*

b. Transformator Step-down

-A1>B6?A=1C?A,-*)0(25A6D>7B9=5>DAD>;1>C571>71><9BCA9; 171> B545A81>1 B52D18 CA1>B6?A=1C?A,-*)0( 49CD>:D;;1> @141

)-)141CA1>B6?A=1C?A,-*)0(:D=<18<9<9C1>@A9=5A<5298 21>G1;41A9@141:D=<18<9<9C1>B5;D>45A_*,

)A9>B9@;5A:1CA1>B6?A=1C?A141<18B52171925A9;DC

$D=@1A1>@A9=5A498D2D>7;1>45>71>C571>71>=1BD;1>25AD@1 1ADB2?<1;21<9;25B1A41>1A18>G1B5<1<D25AD218D218

(<58;1A5>11ADBG1>725AD218D218@1419>C925B9C5A:149@5AD2181> :D=<1871A9B71G1=17>5C9;B531A1C5ADB=5>5ADB;921C>G1@141 ;D=@1A1>B5;D>45AC5A:14977<9>4D;B941>1ADB9>4D;B9B521719;5<D1A1> ).-*.-41A9CA1>B6?A=1C?A

)5A21>49>71>1>C1A1C571>71>@A9=5A_*41>C571>71>B5;D>45A _,@141CA1>B6?A=1C?AB1=145>71>@5A21>49>71>1>C1A1:D=<18<9<9C1> @A9=5A_*41><9<9C1>B5;D>45A_,,531A1=1C5=1C9B41@1C49CD<9B B52171925A9;DC

* *

, ,

J

$5C5A1>71>

_* C571>71>@A9=5A/ * :D=<18<9<9C1>@A9=5A

_, C571>71>B5;D>45A/ _, :D=<18<9<9C1>B5;D>45A

#9;1@141CA1>B6?A=1C?A491>771@C941;1415>5A79<9BCA9;G1>725A D218=5>:1495>5A7925>CD;<19>CA16?9451<25A<1;D8D2D>71>B521719 25A9;DC

41G1@A9=5A41G1B5;D>45A

_@B1C1D_@@BB J

$5C5A1>71>

_* 41G1@A9=5A0

, 41G1B5;D>45A0

* 1ADB@A9=5A

_, 1ADBB5;D>45A

Gambar 6.11 Transformator

Gambar 6.12

Bagan transformator step-up

primer

N_p

sekunder

N_s

Gambar 6.13

Bagan transformator step-down Sumber: PHYWE, 1989

primer

N_p

sekunder

Aktivitas Fisika 6.2

Membuat Transformator Tujuan Percobaan

Membuat transformator step-up.

Alat-Alat Percobaan

1. Kawat tembaga kira-kira 1 m 2. Sumber tegangan 12 V (AC) Langkah-Langkah Percobaan

1. Susunlah peralatan seperti gambar berikut.

2. Lilitkan 10 lilitan kawat pada bagian kiri inti besi, sebagai kumparan primer. Kemudian, sebanyak 20 lilitan pada bagian karena inti besi yang lain, sebagai kumparan sekunder. Hubungkan dengan sumber tegangan.

3. Catat besar tegangan yang terbaca pada voltmeter.

4. Teruskan menambah 10 lilitan pada kumparan sekunder hingga menjadi 50 lilitan. Amati dan catat besar tegangan yang terbaca pada voltmeter. 5. Masukkan data hasil pengamatan Anda pada tabel. Kemudian, buatlah grafik

tegangan sekunder terhadap jumlah lilitan sekunder.

6. Berikan kesimpulan Anda dari kegiatan ini.

kumparan

inti besi

voltmeter

No 1. 2. 3. 4.

Jumlah Lilitan Sekunder 20

30 40 50 Data Percobaan

Besar Tegangan Sekunder ....

.... .... ....

Contoh

6.7

,52D18CA16?BC5@4?F>1;1>497D>1;1>D>CD;=5>G1<1;1>A149?/41A9BD=25A )%'/-5>CD;1>

1 @5A21>49>71><9<9C1>@A9=5A41>B5;D>45ACA16?C5AB52DC 2 :D=<18<9<9C1>@A9=5A:9;1<9<9C1>B5;D>45A>G1<9<9C1>

3 1ADBG1>7497D>1;1>A149?:9;149;D=@1A1>@A9=5AC5A41@1C1ADBB525B1A

1

9;5C18D9

*/,<9<9C1>,/*

1 )5A21>49>71>C571>71>B521>49>745>71>@5A21>49>71>:D=<18<9<9C1> /

/

* * *

, , ,

#149@5A21>49>71>*B

2 5A41B1A;1>81B9<@5A89CD>71>21791>=1;1

*

*

#149:D=<18<9<9C1>@A9=5A<9<9C1>

3 .>CD;=5>789CD>71ADB<9BCA9;41@1C497D>1;1>@5AB1=11>

*,1C1D**,,

/

/ * ,

,

, * ,

#1491ADBG1>7497D>1;1>A149?141<18

Tantangan

untuk Anda

Anda memiliki walkman yang menggunakan baterai 3 V. Bagaimana caranya agar

)141;5>G1C11>>G1C941;141CA1>B6?A=1C?AG1>79451<,521791>5>5A79 <9BCA9;25AD218=5>:14925>CD;5>5A79<19>41<1=CA1>B6?A=1C?A=9B1<>G1 5>5A79@1>1B#149D>CD;CA1>B6?A=1C?AC941;9451<B5<1<D25A<1;D41G1 B5;D>45A<5298;539<41A9@14141G1@A9=5A,*B589>771569B95>B9>G1

<5298;539<41A9

69B95>B9B52D18CA1>B6?A=1C?A494569>9B9;1>B52171981B9<217941G1 <9BCA9; B5;D>45A 45>71> 41G1 <9BCA9; @A9=5A 69B95>B9 CA1>B6?A=1C?A 49>G1C1;1>41<1=@5AB5>B531A1=1C5=1C9B49CD<9B

, *

J

$5C5A1>71>

569B95>B9CA1>B6?A=1C?A , 41G1<9BCA9;B5;D>45A

_* 41G1<9BCA9;@A9=5A

Contoh

6.8

Tidak ada transformator yang efisiensinya 100% karena sebagian energi listrik berubah menjadi bentuk energi lain.

Ingatlah

,52D18CA1>B6?A=1C?A41<1=B52D18A149?CA1>B9BC?A41@1C=5>7D218C571>71>41A9 /=5>:149/#D=<18<9<9C1>B5;D>45A>G1<9<9C1>C5A>G1C1;D1C1ADBG1>7 =5>71<9A@141A149?#9;1569B95>B9CA1>B6?A=1C?AC5AB52DCC5>CD;1> 1 ;D1C1ADB<9BCA9;@141;D=@1A1>@A9=5A

2 41G1@A9=5A41>41G1B5;D>45A

1

9;5C18D9

*/,<9<9C1>,/, 1 -A1>B6?A=1C?AC941;25AB961C9451<=1;125A<1;D

, , ,

* * *

/

_/ *

*

#149;D1C1ADB<9BCA9;@141;D=@1A1>@A9=5A141<18 2 .>CD;=5>789CD>741G1@141B5C91@;D=@1A1>41@1C497D>1;1> @5AB1=11>

***/0

#14941G1@A9=5A>G1141<180

,,,/0

#14941G1B5;D>45A>G1141<180

c. Arus Pusar pada Transformator

)5A81C9;1>21C1>7;?>4D;C?A1>C1A14D1=D;1;DCD25<5;CA?=17>5C9; B5@5AC9G1>749CD>:D;;1>@141)-#9;1=541>=17>5C9; 1>C1A1 =D;1 ;DCD2 9CD 25AD218 C5A8141@ F1;CD 6<D;B G1>7 =5<1<D9 B5=21A1>7B9=@1<C5ACDCD@41<1=21C1>71;1>25AD218:D71B589>771 C9=2D<1ADBADB9>949>1=1;1>45>71>+.,21C1D1ADB@DB1A

ADB @DB1A G1>7 C5A:149 @141 9>C9 CA16? =5AD79;1> B5212 CA16? ;589<1>71>5>5A791C1D41G1>G1=5>:149@1>1B#9;1@1>1B9>93D;D@ C9>779CA16?41@1CC5A21;1AB589>771ADB1;

.>CD;=5>35718;5AD791>41G121C1>7;?>4D;C?ACA1>B6?A=1C?A 492D1C25A<1@9B<1@9BB5@5AC9@141)- 91>C1A1<1@9B1> @5<1C<?71=4925A99B?<1B9&%+B589>771<9>7;1A1>1ADB@DB1A=5>:149

Gambar 6.14

(a) Trafo dengan inti besi. (b) Trafo dengan inti besi berupa lempengan yang terpisahkan oleh laker.

arus pusar inti besi kumparan

1

;539<5>71>31A1B5@5AC99>9;5AD791>41G11;921C1ADB@DB1A41@1C 49;DA1>79

-941;B5=D11ADB@DB1A25AB961C=5AD79;1>@1412525A1@1@5A1<1C1> G1>7 =5>77D>1;1> @A9>B9@ 9>4D;B9 5<5;CA?=17>5C9; 1ADB @DB1A G1>7 C9=2D<41@1C=5>7D>CD>7;1>B5@5AC9@141A5==17>5C9;CD>7;D<9BCA9; 41>B5CA9;1<9BCA9;

3. Transmisi Daya Listrik Jarak Jauh

-A1>B=9B941G1<9BCA9;:1A1;:1D8=5AD@1;1>@A?B5B@5>G1<DA1>41G1 <9BCA9;;5C5=@1CCD:D1>C5AC5>CDG1>7:1A1;>G1:1D841A9@DB1C@5=21>7;9C <9BCA9; %9BCA9; G1>7 B1=@19 49 AD=18AD=18 @5>4D4D; 141<18 81B9< CA1>B=9B941G1<9BCA9;:1A1;:1D8

414D131A1=5>CA1>B=9B9;1>41G1<9BCA9;:1A1;:1D8G19CD 45>71>;D1C1ADB<9BCA9;25B1AG1>74981B9<;1>?<5875>5A1C?A 45>71>C571>71>G1>7<5298C9>77941A9C571>71>G1>74981B9<;1>

?<5875>5A1C?A

)141D=D=>G1CA1>B=9B941G1<9BCA9;:1A1;:1D8=5>77D>1;1>C571>7 1>C9>779$5D>CD>71>G1>749@5A?<5845>71>=5>77D>1;1>CA1>B=9B9 C571>71>C9>779141<181ADB<9BCA9;G1>7=5>71<9A=5<1<D9;1F1CA5<1C96 ;539<B589>771D;DA1>;1F1CCA1>B=9B9G1>7;539<:D7141@1C=5=25A9;1> 1>771A1>291G1:1D8<52985;?>?=9B41>41G1<9BCA9;G1>789<1>7B5@1>:1>7 ;1F1CCA1>B=9B9:1D8<5298;539<B589>77149@5A?<58569B95>B941G1<9BCA9; G1>725B1A

)141@A?B5BCA1>B=9B941G1<9BCA9;:1A1;:1D8497D>1;1>CA1>B6?A=1C?A BC5@D@G1>7C5A41@1C49@DB1C@5=21>7;9CG1>7=5>19;;1>C571>71> 89>771=5>31@19B5;9C1A/$5=D491>41G1<9BCA9;49CA1>B=9B9;1> ;5;?C1;?C1CD:D1>9;?C1;?C1CD:D1>497D>1;1>CA1>B6?A=1C?ABC5@ 4?F>G1>749@1B1>74971A4D71A4D<9BCA9;B589>771C571>71><9BCA9;B91@ 497D>1;1>@141C571>71>B5;9C1A/

Gambar 6.15 Bagan transmisi daya listrik jarak jauh

transmisi tegangan tinggi

generator

transformator transformator gardu listrik

rumah pabrik

tiang listrik pusat

pembangkit listrik

Contoh

6.9

,52D1875>5A1C?AG1>741@1C=5>781B9<;1>41G1<9BCA9;&049CA1>B=9B9;1>=5<1<D9 @5>781>C1A45>71>81=21C1> !9CD>7<18@5AB5>C1B541G1G1>789<1>7

=5>:149;1<?A:9;1

1 C571>71>G1>7497D>1;1>CA1>B=9B9;/

2 C571>71>49>19;;1>?<58CA16?BC5@D@=5>:149;/

1

9;5C18D9&0+

1 )5AB5>C1B541G1<9BCA9;G1>789<1>7:9;1497D>1;1>C571>71>CA1>B=9B9;/ 41@1C4989CD>7B52171925A9;DC

CA1>B=9B9 0 _/

Kata Kunci

• generator • Alternating Current

• komutator • transformator/trafo

• transformator step-up

• transformator step-down

• efisiensi transformator • arus pusar (arus eddy)

1G1G1>789<1>7=5>:149;1<?A89<1>7141<18

_89<1>7&0

)5AB5>C1B589<1>7 _&0&0

2 1G1G1>789<1>7:9;1C571>71>CA1>B=9B949>19;;1>=5<1<D9CA16?=5>:149 ;/141<18

CA1>B=9B9 _/ 0

1G1G1>789<1>7=5>:149;1<?A89<1>7141<18

_89<1>7200

#149@5AB5>C1B589<1>7 _&0;0

,52D18CA1>B6?A=1C?ABC5@D@=5=9<9;9<9<9C1>@141 ;D=@1A1>@A9=5A>G141><9<9C1>@141;D=@1A1> B5;D>45A>G1$D=@1A1>@A9=5A4925A91ADB2?<1;21<9; 25AC571>71>/

1 5A1@1C571>71>;D=@1A1>B5;D>45A

2 #9;11ADB41<1=;D=@1A1>B5;D>45A25A1@1 1ADBG1>7=5>71<9A41<1=;D=@1A1>@A9=5A 3 5A1@1 41G1 =1BD;1> 41> 41G1 ;5<D1A1>

CA1>B6?A=1C?A

,52D18CA1>B6?A=1C?A498D2D>7;1>45>71>BD=25A C571>71>)%'/41>;D1C1ADB>G1-5A>G1C1 C571>71>;5<D1A1>>G1B525B1A/41>;D1C1ADB>G1

!9CD>7

1 569B95>B9CA1>B6?A=1C?A

2 @5A21>49>71>:D=<18<9<9C1>@A9=5A41> B5;D>45A

,52D18 CA1>B6?A=1C?A G1>7 49@1B1>7 @141 A149? =5=9<9;9 B@5B969;1B9 / C5A=9>1< @A9=5A>G1 498D2D>7;1>45>71>BD=25A)%'/#9;1:D=<18 <9<9C1>B5;D>45ACA1>B6?A=1C?AC5AB52DC<9<9C1>41> 1ADBG1>7=5>71<9A41<1=A149?C5>CD;1> 1 :D=<18<9<9C1>@A9=5A

2 ;D1C1ADB@141;D=@1A1>@A9=5A

3 41G1@A9=5A41>41G1B5;D>45A:9;1569B95>B9 CA1>B6?A=1C?A

Tes Kompetensi

Subbab

B

"-&'*($!()0'0(/%$*

C. Arus dan Tegangan Listrik Bolak-balik

ADB 41> C571>71> <9BCA9; 2?<1;21<9; =5=9<9;9 >9<19 G1>7 B5<1<D 25AD218D218 C5A8141@ F1;CD B531A1 @5A9?49; 219; 25B1A =1D@D> 1A18>G15B1A1>1ADB41>C571>71>2?<1;21<9;49<1=21>7;1>45>71> 5F1B19>981=@9AB5=D1@5A1<1C1>AD=18C1>77149?@5A1B9;1> 45>71>5>5A79<9BCA9;1ADB2?<1;21<9;,5@5AC9>41;5C18D9@5A25411> =5>41B1A1>C1A11ADB2?<1;21<9;41>1ADBB51A18141<18@?<1A9C1B>G1

.>CD;=5>75C18D9@?<1A9C1B1ADBB51A18G1>7B5<1<DC5C1@41>1ADB 2?<1;21<9;G1>7B5<1<D25AD21841@1C497D>1;1>?B9<?B;?@-")2 ,#&),)* &5<1<D9 1<1C 9>9 41@1C :D71 491=1C9 >9<19 6A5;D5>B9 41> @5AD2181>C571>71>@141B5C91@B11C41<1=25>CD;7A169;41@D>D>CD; =5>7D;DA >9<19 C571>71> 565;C96 41> ;D1C 1ADB <9BCA9; 565;C96 41@1C 497D>1;1>E?<C=5C5A41>1=@5A5=5C5A

1. Sumber Tegangan Bolak-Balik (AC)

Gambar 6.18 Pengukuran arus listrik dengan menggunakan volmeter.

1 2

)5A81C9;1>)-(B9<1B971G175A1;<9BCA9;41>1ADB2?<1; 21<9;4981B9<;1>41A9B52D18;D=@1A1>G1>725A@DC1A45>71><1:DC5C1@ )14171=21A7A169;C5AB52DC@D>31;41>B9=@D<75<?=21>7=5>D>:D;;1> ;54D4D;1>;D=@1A1>C5A8141@25B1ABD4DCG1>749C5=@D8>G1

5B1A 77< G1>7 4981B9<;1> 41A9 B52D18 75>5A1C?A G1>7 25A@DC1A =5=5>D89@5AB1=11>25A9;DC

J

1C1DD>CD; - J

;1A5>1 3?B=1;1

3?B

J

1C1D J

3?B -

J

#9;1;9C1CDAD>;1>"-.)*3 4941@1C B9>

J

C1D41@1C:D7149CD<9B;1>45>71>

=1;BB9>

J1

$1A5>177<9>4D;B9B1=145>71>2541C571>71>491>C1A14D1;DCD277< 9>4D;B9=1;141@1C49CD<9B

=1;BB9>

J2

$5C5A1>71>

'%,

71G175A1;<9BCA9;=1;B9=D=E?<C

E?<C

_'%,C571>71>=1;B9=D=E?<C

6<D;B=17>5C9;02

:D=<18<9<9C1>;D=@1A1> <D1B2941>7;D=@1A1>=

6A5;D5>B9BD4DC@DC1A1>;D=@1A1>A14 B

-#9;1 75>5A1C?A C5AB52DC 498D2D>7;1> 45>71> A1>7;191> C5ACDCD@ 1;1>=5>71<9A1ADB

2. Alat Ukur Tegangan dan Arus Bolak-Balik

.>CD;=5>75C18D9141>G1C571>71><9BCA9;@141BD1CDA1>7;191> B1<18B1CD>G1497D>1;1>B52D181<1CG1>749B52DC-,-*()- ;1>C5C1@9C5BC@5>C941;41@1C=5>75C18D925B1A>G1C571>71>G1>7 =5>71<9A@141A1>7;191>C5AB52DC41@D>D>CD;=5>7D;DA>9<19C571>71> 41>;D1C1ADB497D>1;1>E?<C=5C5A41>1=@5A5=5C5A'9<19 G1>7C5A2131@1411<1CD;DA9>9=5>D>:D;;1>81A71565;C9641A9C571>71> 41> ;D1C 1ADB &5<1<D9)- >41 41@1C =5=181=9 81B9< @5>7D;DA1>1ADB<9BCA9;41<1=B52D18A1>7;191>

Gambar 6.16 Grafik tegangan dan arus listrik bolak-balik terhadap waktu.

1

2

V V_m V = V_msint

T 2T

I _I

m I = Im sint

T 2T

bagian atas yang berlogam

bagian tengah yang transparan

lampu

logam

Gambar 6.19

Pengukuran tegangan pada sebuah rangkaian

resistor

voltmeter

1A9@5>71=1C1>=5<1<D9?B9<?B;?@BD=2DE5AC9;1<491CDA@141C571>71>/ 3=

Contoh

6.10

Gambar 6.20

kWh meter yang ada di rumah digunakan untuk mengukur daya listrik yang terpakai.

)141)-C5A=9>1<;DCD2@?B9C96498D2D>7;1>45>71> 1ADB=1;B9=D=@1411=@5A5=5C5AC5A2131>9<191ADBB541>7 ;1>)-C5A=9>1<@?B9C96498D2D>7;1>45>71>1ADB=1;B9=1< C5A>G1C1C5A2131>9<191ADB)5>7D;DA1>9>9=5>D>:D;;1>218F1 1>7;1G1>7C5A2131@1411<1CD;DA141<18>9<19565;C96>G15=9;91> @D<141<1==5>7D;DAC571>71>B52D18A1>7;191>B5@5AC9)- $5C9;11ADB=5>71<9A:1AD=@5>D>:D;E?<C=5C5A=D<1925AD218'9<19 G1>7C5A2131=5>D>:D;;1>81A71565;C96C571>71>A1>7;191><9BCA9;>41 41@1C:D71=5>7D;DA;D1C1ADBC571>71>41>81=21C1><9BCA9;219; 1ADB =1D@D> 1ADB 45>71> =5>77D>1;1> =D<C9=5C5A =@5A5=5C5A/?<C=5C5A41>(8==5C5A41>?B9<?B;?@

3. Nilai Efektif Tegangan dan Kuat Arus AC

<1C D;DA G1>7 497D>1;1> D>CD; =5>75C18D9 :D=<18 41G1 G1>7 C5A@1;19 @141 ;52DCD81> 5>5A79 <9BCA9; 49 AD=18 141<18 ;08 =5C5A 5A5C1>1>7;1=5>D>:D;;1>25B1A5>5A79<9BCA9;G1>7C5A@1;19

)5A81C9;1>)- -1=@1;:5<1B1>7;1G1>7=5>D>:D;;1> 25B1A5>5A79<9BCA9;G1>7C5A@1;1941<1=B1CD1>;08%#&)--").+ >5A799>949@5A?<5841A9>9<19 41> !1A71565;C961ADB1C1DC571>71> 2?<1;21<9;141<18;D1C1ADB1C1DC571>71>2?<1;21<9;G1>7491>771@ B5C1A145>71>1ADB1C1DC571>71>B51A18G1>7=5>781B9<;1>:D=<18;1<?A G1>7B1=1;5C9;1=5<1<D9BD1CD@5>781>C1A41<1=F1;CDG1>7B1=1

,52D18@5>781>C1AB5@5AC9)- =5=9<9;981=21C1>41<1= F1;CD-5B1A5>5A79;1<?AG1>74981B9<;1>?<581ADB565;C96>G1141<18

Gambar 6.21

(a) Sebuah rangkaian dengan hambatan R;

(b) Grafik hubungan I dengan t.

1

A B I

I_m I_ef

t

2

1 2t

_msin t R

B541>7;1>B5<1>7F1;CD=5>D>:D;;1>=B 3=,;1<1C91@;?C1;=5=9<9;9D;DA1> 3=K3=-5>CD;1>

1 C571>71>=1;B9=D= 2 6A5;D5>B9BD=25A

1

9;5C18D9_**/ 3=

1 )14171=21AC5A2131C571>71>@D>31;_**141<183=;1A5>1B;1<1E5AC9;1< / 3==1;1

_**3=K/ 3=E?<C#149C571>71>=1;B9=D=>G1141<18

_'%,**//

2 )5A9?4541<1=7A169;3=,;1<18?A9H?>C1<=B 3==1;1

3=K=B 3==BB

#1496A5;D5>B9BD=25A !H

- J

>5A79;1<?AG1>74981B9<;1>41<1=A1>7;191>1ADB=5=9<9;9>9<19 G1>7B5<1<D25AD218B531A1@5A9?49;41<1=F1;CD 41>=5=5>D89

@5AB1=11>

- _J

"-.)*341>"-.)*3=5=9<9;9>9<19G1>7B1=1 B589>77141@1C49@5A?<5825B1A1ADB565;C96>G1

56

-

56

-

=1;B

- J

45>71>=5>77D>1;1>31A1=1C5=1C9;149@5A?<581ADB565;C96 B521719 25A9;DC

=1;B

J 5>71>31A1G1>7B1=1C571>71>565;C96 1;1>49@5A?<58@5AB1=11>

=1;B J

,52D18A1>7;191>G1>7498D2D>7;1>45>71>BD=25A<9BCA9;2?<1;21<9;49D;DA 45>71>E?<C=5C5A41>=5>D>:D;;1>1>7;1E?<C5A1@1;1881A71=1;B9=D= C571>71>2?<1;21<9;BD=25A41>CD<9B;1>@5AB1=11>>G1:9;16A5;D5>B9>G1!H

1

9;5C18D9

/

!H

1 '9<19C571>71>=1;B9=D=_=1;B4989CD>745>71>=5>77D>1;1>"-.)* 3B589>77149@5A?<58

_=1;B

/

2 )5AB1=11>C571>71>49@5A?<5845>71>=5>77D>1;1>"-.)*3 G19CD

_=1;BB9>

B9>

-Contoh

6.11

Tantangan

untuk Anda

Gambar 6.22 Grafik hubungan I dan t I_maks = kuat arus maksimum

I_r = kuat arus rata-rata.

I

I_maks I_r

t +74F3:C3@9=3;3@3CFD4A>3=43>;=?7?;>;=;:3C93E793@93@D74393;8F@9D;H3=EF

J3;EF D;@.!;EF@9>3: 3 E793@93@?3=D;?F?_%#* 4 E793@93@BF@53==7BF@53=₍₍ 5 E793@93@787=E;8

6 8C7=F7@D;3@9F>7C 7 B7C;A67

8 8C7=F7@D;

9 E793@93@D7E7>3:+D7=A@

#7#$

7@93@?7@J3?3=3@B7CD3?33@E793@93@J3@96;=7E3:F;E7C:363B'34#/##0 9?3=36;B7CA>7:

_%D;@+ D;@+ 63C;B7CD3?33@E7CD74FE6;B7CA>7:

.63@C36 D 3 _% .

4 _((% . . 5 . .

%

6 C36 D

7

_D

8 !K

9 D;@+ D;@.

Contoh

6.12

1 2t

4. Harga Kuat Arus dan Tegangan Rata-Rata

!3C93=F3E3CFD4A>3=43>;=C3E3C3E3363>3:=F3E3CFD4A>3=43>;= J3@9 @;>3;@J3 D7E3C3 67@93@ =F3E 3CFD D73C3: F@EF= ?7?;@63:=3@ ?F3E3@ >;DEC;= J3@9 D3?3 63>3? H3=EF J3@9 D3?3 )7C:3E;=3@ 9C38;= D;@FDA;6363C;3CFDD7>3?3 D7=A@#/$#3

-@EF=3CFDD73C3:D7E7>3: D7E7@93:B7C;A67?F3E3@J3@9 6;>3>F;@J3?7?7@F:;B7CD3?33@

) N

63BF@<F?>3:?F3E3@J3@96;>3>F;3CFD4A>3=43>;=63>3?C3@9=3;3@ 363>3:

%#*

Tugas Anda

Arus listrik bolak-balik dapat diamati menggunakan osiloskop. Bersama kelompok belajar Anda, gunakan osiloskop yang ada di laboratorium sekolah Anda untuk mempelajari penggunaan osiloskop tersebut. Catatlah hal-hal yang Anda anggap penting. Mintalah bimbingan guru Fisika Anda untuk melakukan tugas ini.

3C;'34#/##0 9 63@'34#/##0 9 3=3@6;B7CA>7:B7C D3?33@3CFDC3E3C3E3D74393;47C;=FE

₎

%#*

D;@

++ N

7@93@?7@99F@3=3@53C3?3E7?3E;=36;B7CA>7:

₎%#* _N

7@93@B7@<343C3@J3@9D3?33=3@6;B7CA>7:B7CD3?33@E793@93@ C3E3C3E3F@EF=3CFDD747D3C

₎%#* _N

$7E7C3@93@

) E793@93@C3E3C3E3.

_%#*E793@93@?3=D;?F?.

)7CD3?33@E793@93@4A>3=43>;=DF3EFC3@9=3;3@>;DEC;=?7?7@F:;B7CD3?33@

D;@.,7@EF=3@E793@93@C3E3C3E3J3@96;:3D;>=3@DF?47CE7CD74FE #7#$

;=7E3:F;D;@._%#*. 7@93@?7@99F@3=3@'34#/##09 6;B7CA>7:

₎%#* .

.

Contoh

6.13

5. Diagram Fasor

-@EF=?7?B7C?F63:?7@93@3>;D;D3C3:E793@93@63@=F3E3CFD 6;9F@3=3@?7EA676;39C3?83DAC3DAC(!*-#+')363>3:DF3EF47D3C3@ J3@96;>F=;D=3@D74393;DF3EFG7=EACJ3@947D3CDF6FEBFE3C@J3E7C:363B DF?4F:AC;KA@E3>D3?367@93@DF6FE83D7@J3 +3DACDF3EFG7=EAC

47CBFE3C47C>3H3@3@3C3:<3CF?<3?67@93@=757B3E3@DF6FE

E7E3B

6;93?43C=3@A>7:D74F3:3@3=B3@3:F@EF=?7@J3E3=3@E793@93@63@ =F3E3CFD63C;DF3EFC3@9=3;3@>;DEC;=)363#/$#3 63B3E@63 B7C:3E;=3@6;39C3?83DAC63C;E793@93@63@3CFD4A>3=43>;=

+F?4F:AC;KA@E3>B363 #/$#3 363>3:F@EF=?7@7@EF=3@ 47D3C@J3 DF6FE 83D7 J3@9 6;F=FC 63>3? D3EF3@ 67C3<3E 3E3F C36;3@ D763@9=3@DF?4FG7CE;=3>F@EF=?7@7@EF=3@@;>3;E793@93@63@=F3E 3CFDJ3@9?7CFB3=3@47D3C3@D=3>3C4F=3@G7=EAC&7>3>F;?7EA67 6;39C3?83DAC;@;6;:3C3B=3@@6363B3E?7?3:3?;3C3:83D7G7=EAC 67@93@?F63:

6. Resistor pada Rangkaian Arus Bolak-Balik

)363#/$#3D74F3:C7D;DEAC?FC@;6;B3D3@963>3?C3@9=3;3@ E7CEFEFB3CFD4A>3=43>;= C38;=E793@93@DF?47CJ3@947CD;83ED;@FDA;63 3=3@?7@9:3D;>=3@3CFDJ3@9<F9347CD;83ED;@FDA;63

Gambar 6.23 Grafik fasor I dan V

I_m V_m

t

Gambar 6.24 Rangkaian arus AC dengan hambatan murni R.

a b

I

)7CD3?33@E793@93@4A>3=43>;=3@E3C3F<F@9F<F@9C7D;DEAC?FC@;

363>3:

_%D;@

+ N

7@93@?7?7C:3E;=3@6-6/*/J3@9?7@J3E3=3@43:H3=F3E3CFD J3@9?7@93>;C?7?;>;=;:F4F@93@67@93@_% %

?3=347D3C

3CFD4A>3=43>;=J3@9?7@93>;C?7>3>F;C3@9=3;3@?7?7@F:;B7CD3?33@

%D;@

+ N

)7C:3E;=3@#/$#3 7C63D3C=3@'34#/##0 9 63@

'34#/##093CFD?3=D;?F?63@E793@93@?3=D;?F??7?;>;=; 83D7J3@9D3?3CE;@J3=7E;=3BAD;D;=F?B3C3@?7@53B3;DF6FE M

E793@93@63@3CFDJ3@9?7>3>F;C3@9=3;3@?7@53B3;@;>3;?;@;?F?%74;: <7>3D@J3@63B7C:3E;=3@#/$#3;39C3?83DAC63C;=F3E3CFD 63@E793@93@@J3?7?;>;=;3C3:J3@9D3?3

t

Imaks Vmaks

Gambar 6.26 Diagram fasor arus I dan tegangan V memiliki arah yang sama.

Gambar 6.27

Rangkaian arus bolak-balik dipasang seri dengan sebuah induktor murni.

Gambar 6.25

Grafik kuat arus I dan tegangan V

pada rangkaian hambatan murni, arus I, dan tegangan V sefase.

rotasiV_m i_m

V = V_msint i = i_msint

2

3 2

5 2

2 3

t

*7D;DEAC?7CFB3=3@D3>3:D3EF=A?BA@7@>;DEC;=J3@9D7C;@96;9F@3=3@+7E;3B C7D;DEACJ3@96;<F3>6;B3D3C3@?7?;>;=;@;>3;C7D;DE3@D;E7CE7@EF,F93D@634F3E>3: C7DF?7?7@97@3;53C3?7@9;67@E;8;=3D;@;>3;D74F3:C7D;DEAC+7E7>3:?7?4F3E C7DF?7;@;6;:3C3B=3@@6363B3E?7@97@3>;C7D;DEAC63@?3?BF?7@7@EF=3@ @;>3;C7D;DE3@D;@J363C;5;C;5;C;J3@96;?;>;=;C7D;DEACE7CD74FE93C>74;:?7@3C;= D7CE3=3@93?43C?353??353?C7D;DEAC63>3?EF>;D3@@63

Mari Mencari Tahu

a L b

I = I_m sint

7. Induktor Murni pada Rangkaian Arus Bolak-Balik

)7C:3E;=3@#/$#3+74F3:;@6F=EAC?FC@;?7?;>;=;;@6F= E3@D;6;C;)363D33E3CFD>;DEC;=?7@93>;C63>3?C3@9=3;3@3=3@E;?4F> 93J397C3=>;DEC;=;@6F=D;99>6;3@E3C3F<F@9;@6F=EACJ3@947D3C@J3 363>3:

+

63BF@ 4763 E793@93@ 3@E3C3 F<F@9F<F@9 =F?B3C3@ D74393; 8F@9D; H3=EF363>3:

_%D;@

+ N

#;=3@63B7C:3E;=3@C3@9=3;3@3CFD4A>3=43>;=63>3?#/$#3 C3@9=3;3@E7CD74FE?7CFB3=3@C3@9=3;3@E7CEFEFB63@47C>3=F!F=F? ""$;C5:A88!F=F?""$;C5:A88?7@J3E3=3@43:H3

(>7:=3C7@363>3?C3@9=3;3@E7CD74FEC7D;DEAC?FC@;E;63=363J3;EF @;>3;?3=36;B7CA>7:B7CD3?33@=F3E3CFDD74393;47C;=FE

_{*,%)"&,#+') %}D;@

+N₊

+ % D;@

+

Gambar 6.28

Grafik kuat arus I dan tegangan V

pada rangkaian induktif murni. Tegangan V mendahului arus I

sekitar 90°.

I = I_m sint V_m

i_m

2

%

D;@+ +

%

N 5AD ₊

% D;@ ₊

D;@ N

%

+

N

7@93@?7?7C:3E;=3@B7@FCF@3@'34#/##09 6;=7E3:F;43:H3 %

%

&7@FCFE!F=F?(:??7CFB3=3@@;>3;:3?43E;@6F=EAC

J3@96;D74FEC73=E3@D;;@6F=E;8D7:;@99363B3E6;EF>;D

3E3F

N

$7E7C3@93@

C73=E3@D;;@6F=E;8

=757B3E3@DF6FEC36 D ;@6F=E3@D;6;C;!

8C7=F7@D;!K

7@93@?7@93?3E;:F4F@93@'34#/##0963@'34#/##0 9 6;=7E3:F;B7C47633@83D73@E3C3E793@93@63@=F3E3CFDJ3@9 ?7>3>F;C3@9=3;3@;@6F=E;8E7CD74FED747D3C 7@93@DF6FE83D73CFD E7CE;@993>363>3: C3663C;DF6FE83D7E793@93@

@63 3=3@ >74;: ?7?3:3?; <;=3 ?7?7C:3E;=3@ 9C38;= E793@93@ D;@FDA;63>63@9C38;=3CFDD;@FDA;63>E7C:363BH3=EF?7>3>F;#/$#3 #;=3E793@93@B363F<F@9F<F@9C3@9=3;3@?3=D;?F?@;>3;3CFD 63>3?C3@9=3;3@3=3@?;@;?F?+743>;=@J3<;=3E793@93@47C@;>3; ?;@;?F?3CFDJ3@9?7>3>F;C3@9=3;3@3=3@?3=D;?F?_%#* Gambar 6.29

Diagram fasor arus I dan tegangan V. Tegangan mendahului 90°.

V_L

I

90°

)363D74F3:C3@9=3;3@3CFD4A>3=43>;=67@93@8C7=F7@D; !K6;B3D3@9;@6F=EAC D747D3C!*3@9=3;3@;@;?7@9:3D;>=3@3CFD?3=D;?F?!;EF@9E793@93@ ?3=D;?F?;@6F=EACE7CD74FE

#7#$ ;=7E3:F;

8C7=F7@D;

Contoh

6.14

3CFD?3=D;?F?%

;@6F=E3@D;;@6F=EAC!

,793@93@?3=D;?F?63B3E6;:;EF@967@93@B7CD3?33@

_%% %

!K ! .

8. Kapasitor pada Rangkaian Arus Bolak-Balik

)C;@D;B =79F@33@@J3 D3?3 67@93@ ;@6F=EAC $3B3D;EAC 63>3? C3@9=3;3@3CFD4A>3=43>;=6;B3D3@9F@EF=?7?B7CA>7:7@7C9;>;DEC;=J3@9 >74;:47D3CCFD>;DEC;=J3@9?7>3>F;=3B3D;EACJ3@9=3B3D;E3D@J3D747D3C

D7>3?3+3=3@?7@J7434=3@=3B3D;EAC47C;D;?F3E3@D747D3C + N

63BF@?F3E3@J3@9E7CD;?B3@63>3?=3B3D;EAC#/$#3 363>3:

N

6;?3@3

._%D;@

+ N

3C;=76F3'34#/##0963@'34#/##09 63B3E6;B7CA>7:

+

+

%+D;@ +

D;@

+_%

5AD

+

_%

5AD

+

_%5AD

+

_%D;@

+

N

7@93@?7?7C:3E;=3@B7@FCF@3@'34#/##096;=7E3:F;43:H3

_%%

&7@FCFE!F=F?(:? ?7CFB3=3@@;>3;:3?43E3@

=3B3D;EACJ3@96;D74FEC73=E3@D;=3B3D;E;8D7:;@99363B3E6;EF>;D

3E3F N

$7E7C3@93@

C73=E3@D;=3B3D;E;8

=3B3D;E3D=3B3D;EAC

8C7=F7@D;DF6FEC36 D

7@93@?7@93?3E;:F4F@93@'34#/##0963@'34#/##0 96;=7E3:F;B7C47633@83D73@E3C3E793@93@63@=F3E3CFDJ3@9 ?7>3>F;C3@9=3;3@=3B3D;E;8E7CD74FED747D3C 7@93@DF6FE83D73CFD ?7@63:F>F;363>3: C3663C;DF6FE83D7E793@93@

@63 3=3@ >74;: ?7?3:3?; <;=3 ?7?7C:3E;=3@ 9C38;= E793@93@ D;@FD;A63>63@9C38;=3CFDD;@FD;A63>E7C:363BH3=EF?7>3>F;#/$#3

#;=3 E793@93@ B363 F<F@9F<F@9 C3@9=3;3@ ?3=D;?F? @;>3; 3CFD 63>3? C3@9=3;3@ 3=3@ ?3=D;?F? % +743>;=@J3 <;=3 E793@93@ 47C@;>3;?3=D;?F?3CFDJ3@9?7>3>F;C3@9=3;3@3=3@?;@;?F?

Gambar 6.32

Diagram fasor I dan V pada kapasitor.

Gambar 6.31

Grafik I dan V pada kapasitor dalam rangkaian AC. Gambar 6.30 Rangkaian kapasitor

a C b

V = V_msint

V_i

V = V_m sin

t 2

i = i_msint

V

I

Tantangan

untuk Anda

Sebuah kapasitor 100F dihubungkan dengan sumber tegangan bolak-balik. Arus yang mengalir melalui rangkaian memenuhi persamaan

I = 4 sin 200t A. Tuliskan persamaan tegangan kapasitor itu.

+74F3:=3B3D;EAC67@93@6;B3D3@9B363DF?47CE793@93@4A>3=43>;= 67@93@8C7=F7@D; !K,793@93@?3=D;?F? _%.D7B7CE;B36393?43C 47C;=FE

!;EF@93CFD?3=D;?F?B363=3B3D;EACE7CD74FE #7#$

;=7E3:F; ON

!K_%. C36 D

_{C36 D}

(>7:=3C7@3;EF3CFD?3=D;?F?@J3363>3:_% %

Contoh

6.15

V = V_msint 200 c F !#$'.

*3@9=3;3@63@B363*3@9=3;3@CFDA>3=3>;=

1 #0)-#+#0 '#-5#04+ +(#5 _6056-'056-'34#/##04+0

*7D;DEAC D783D7 %D;@+

"@6F=EAC $ E7CE;@993> _%D;@

+

D747D3C C36

$3B3D;EAC ?7@63:F>F; %D;@ + D747D3C

C36

!#$'. ?7@993?43C=3@ B7CD3?33@ 3CFD J3@9 ?7@93>;C 63>3? E;3BC3@9=3;3@#;=3DF?47CE793@93@4A>3=43>;=6;3@993BD3?3J3;EF

_%D;@

+

+747EF>@J3@6363B3E?7@7@EF=3@E7C>74;:63:F>FB7CD3?33@3CFD 43CF=7?F6;3@B7CD3?33@E793@93@@J3&;D3>@J33CFDJ3@9?7@93>;C 63>3?E;3BC3@9=3;3@D3?3_%D;@

+?3=33=3@6;63B3EB7CD3?33@

E793@93@B363

3 C7D;DEAC_%D;@

+

4 ;@6F=EAC_%D;@

+

9.

R

,

L

, dan

C

Dipasang Seri dalam Rangkaian Arus Bolak-Balik

*3@9=3;3@3CFD>;DEC;=4A>3=43>;=J3@9?7?;>;=;:3?43E3@?FC@;

6;B3D3@9D7C;67@93@;@6F=EACD7CE3=3B3D;EAC3=3@?7@9:3D;>=3@ E3?43:3@7@7C9;>;DEC;=J3@9>74;:47D3CE7E3B;C3@9=3;3@//D7C;;@; :3@J363B3E6;9F@3=3@F@EF=?7?B7C47D3C63J3>;DEC;=J3@9E7C43E3D CFD?3=D;?F?63>3?C3@9=3;3@?7?;>;=;@;>3;63@83D7J3@9D3?3B363 D7E;3B=A?BA@7@%74;:<7>3D63B3E@63B7C:3E;=3@#/$#3

#;=3 @63 E7E3B=3@ B7CD3?33@ 3CFD 63>3? C3@9=3;3@ D747D3C

%D;@ + B7CD3?33@D7E;3BE793@93@67@93@?7?7C:3E;=3@6;39C3? 83DACB363#/$#3 J3;EF

_?D;@

+?7?;>;=;83D7J3@9D3?367@93@3CFD _?D;@

+

_{?7@63:F>F;83D7D747D3C}

C36

?D;@

+

E7CE;@993>83D7D747D3C C36

)7C:3E;=3@C3@9=3;3@//D7C;B363#/$#3 +7E;3B=A?BA@7@ ?7?;>;=;E793@93@63@+753C383DACE793@93@E793@93@;@; 63B3E6;<F?>3:=3@D74393;47C;=FE

" " " " N (>7:=3C7@3 " " 63@ "D3>;@9E793=>FCFD:3C9363B3E6; E7@EF=3@67@93@?7@99F@3=3@:;EF@9G7=EACJ3;EF

N

67@93@?7?7C:3E;=3@=7?43>;#/$#3:3?43E3@EAE3>C3@9=3;3@ D7C;NNJ3@96;D74FE67@93@;?B763@D;C3@9=3;3@.63B3E6;:;EF@9 63C;'34#/##09

N3

3E3F

N4

(>7:=3C7@33CFD?3=D;?F?J3@9?7@93>;C6;D7E;3B=A?BA@7@D3?3 47D3C@J3:F4F@93@3@E3C3E793@93@?3=D;?F?63@3CFD?3=D;?F?;@; ?7?7@F:;B7CD3?33@2J3;EF

N

$7E7C3@93@

% E793@93@?3=D;?F?

;?B763@D;C3@9=3;3@

NC73=E3@D;EAE3>

Gambar 6.33 Resonansi rangkaian

R–L–C seri

Gambar 6.35

Diagram fasor Z, R,X_L, dan X_C. Gambar 6.34

Diagram fasor V, V_R, V_L, dan V_C.

Z

X

L – XC

X

L

R X

C

R L C

v

I = I_m sin t

i L

V– VC L

V

V

R

V

C

R = 30 X

L = 40 I

V

L

V

R

V = V_msint

76383D73@E3C3E793@93@63@=F3E3CFD63B3E6;E7@EF=3@D74393; 47C;=FE

E3@

_N

D7:;@993B7CD3?33@E793@93@@J3363>3: %D;@

+

B34;>3DF6FE83D747C@;>3;BAD;E;8CE;@J3E793@93@

?7@63:F>F;3CFD63@C3@9=3;3@47CD;83E;@6F=E;8#;=3DF6FE83D7

47C@;>3;@793E;8CE;@J3E793@93@E7CE;@993>A>7:3CFD63@C3@9=3;3@

47CD;83E=3B3D;E;8#;=36;B7CA>7:63@CE;@J3 E793@93@?7?;>;=;83D7D3?3D763@9=3@C3@9=3;3@47CD;83EC7D;DE;83>3? :3>;@;6;=3E3=3@E7>3:E7C<36;C7DA@3@D;

10.

R

dan

L

Dipasang Seri dalam Rangkaian Arus Bolak-Balik

)7C:3E;=3@#/$#3 +7E;3B=A?BA@7@?7?;>;=;E793@93@

63@+753C383DACE793@93@E793@93@;@;63B3E6;<F?>3:=3@D74393;

"""7@93@?7@99F@3=3@:;EF@93@G7=EAC47D3C@J3E793@93@ EAE3>J3;EF

N

7D3C@J3;?B763@D;C3@9=3;3@*N%6;B7CA>7:D7B7CE;47C;=FE