Fisika · Bab 6 Cahaya dan Optika

Dudi Indrajit

24/08/2021 14:18:42

SMA 10 KTSP

Daftar Isi

Bab 1 Pengukuran dan Besaran Bab 2 vector Bab 3 Gerak Lurus Bab 4 Gerak Melingkar Bab 5 Dinamika Gerak Bab 6 Cahaya dan Optika Bab 7 Kalor Bab 8 Listrik Dinamis Bab 9 Gelombang Elektromagnetik

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A. CahayaB. PemantulanCahayaC. PembiasanCahayaD. Alat-Alat OptikCahaya dan Optika,5C91@81A9=1>DB91C941;1;1>@5A>18C5A<[email protected]41A93181H1 5>4125>4149B5;5<9<9>7>41[email protected]C5A<981C;1A5>1141>H13181H1 181H1:D71H1>7=5=2D1C>41[email protected]=5<981C21H1>71>>414935A=9> &D>7;9>>41@5A>18=5=5A81C9;1>;131[email protected]?>@141=?29<1C1D[email protected]=?C?A $131[email protected]?>@141=?29<41>[email protected]=?C?A[email protected];1>B52D1835A=9>35=2D>7H1>7497D>1;1>@5>75=D49D>CD;=5<981C<1<D<9>C1B4925<1;1>7=?29<1C1D[email protected]=?C?A 5>71>=5<981C;131[email protected]?>@5>75=D49[email protected]25A25<?;25A85>C91C1D=5>418D<D9;5>41A11><19>45>71>1=1> )141;131[email protected]?>C5A:149@5=1>CD<1>3181H1B589>771>41[email protected]=5<981C21H1>71>25>4125>41H1>725A14149[email protected]>>H1 [email protected];18>41=5>7945>C969;1B9B961CB961C21H1>71>@14135A=9>;131[email protected]?>,5<19>35A=9>35=2D>725A41B1A;1>25>CD;>H11414D1:5>9B35A=9><19>>H1H19CD35A=9>41C1A41>35A=9>35;D>7 [email protected];18;54D135A=9>9>9=5>5ADB;1>3181H11719=1>1B961CB961C21H1>71>>H1>41[email protected]=5>5>CD;1>:1F121>@5AC1>H11>@5AC1>H11>C5AB52DC41<1=2129>9 (<58;1A5>19CD@5<1:1A9<182129>945>71>219; 107•menganalisis alat-alat optik secara kualitatif dan kuantitatif;•menerapkan alat-alat optik dalam kehidupan sehari-hari.Setelah mempelajari bab ini, Anda harus mampu:menerapkan prinsip kerja alat-alat optik.Hasil yang harus Anda capai:Pengemudi memanfaatkan pemantulan cahaya pada cermincembung kaca spion.Bab6Sumber: Dokumentasi Penerbit

108Mudah dan Aktif Belajar Fisika untuk Kelas XA. Cahaya,19>B41>C5;>?<?79B5<1<D=5=21F1>41D>CD;[email protected]=5=181=91<1= !1<9>949B5212;1>B19>B41>C5;>?<?79B5<1<D=5=25A9@5>75C18D1>21ADB5AC19>BCAD=5>21ADH1>7[email protected]=5>7D>7;1@A181B91A181B911<1=B5;1<[email protected]>75:1<11<1=H1>7B5=D<1491>771@C941;=D>7;9>C5AD>7;1@ 5>?=5>11BCA?>?=9[email protected]<529821>H1;C5AD>7;1@;1A5>1C5AB5491>H1C5<5B;?@1C1DC5A?@?>7H1>7<5298219;[email protected]B525<D=>H1 $5=1:D1>41>@5>5=D1>41<1=29?<?79=?45A>C941;[email protected]C5A:149:9;1C941;141=9;A?B;?@ 1719=1>11<1C1<1C[email protected];C5AB52DC25;5A:141>[email protected]=5>7D>7;1@A181B911<1=1<1=2129>91;1>492181BB5:D=<188D;D=B5AC1@A9>B9@?@C9;175?=5CA9@5=1>CD<1>41>@5=291B1>H1>749C5A1@;1>41<1=[email protected]1<1C[email protected]; 1. Teori-Teori tentang Cahaya5A9;DC1;1>49:5<1B;1>[email protected]C5?A9C5>C1>73181H1 a.Teori Partikel)141)5AC5>7181>1214;5 &89>771@5AC5>7181>1214;5L &B5:1A189B9;1B1>71C[email protected]>71AD89?<58@5=9;9A1>41>;1AH15$$&'(9621=5B;[email protected]>[email protected]B5:D=<18C?;?825B1A<19>H1>7894D@B5I1=1>45>71>'5FC?>H1>7=5=25A9;1>;?>CA92DB925B1AC5A8141@9B9;1 ;1>[email protected]491>C1A1=5A5;1141B521791>H1>7C941;[email protected]>[email protected]45>71>(9621491>C1A1>H1 2%(4622.( 2%(462:/(+4,56,$17:*(15/( 2(0(4$0(54$'/(:41>'021'$//(:)141 (9621=5>5A29C;1>;1AH19<=918@5AC1=1C5>C1>73181H141>F1A>141<1=%&),/,-%& ) .+/ 0&,+/ $5A:19<=9189>949C5A9=145>71>219;?<58B5=D1@981;;53D1<922.(41>7:*(15 &5A5;1;525A1C1>45>71>(962125A;19C1>45>71>@5A3?211>H1>7=5=2D;C9;1>218F13181H1C5A49A91C1B@1AC9;5<;539<H1>725A75A1; &5A5;1=5>71>771@218F13181H1[email protected];1>75<?=21>7 -5?A9@1AC9;5<[email protected]=5>:5<1B;1>218F1@5A1=21C1>3181H1[email protected]71A9B<DADBH1>7C941;[email protected]49<981C41A925<1;1>7B52D18@5>781<1>7 [email protected]>75<?=21>7[email protected]75<?=21>72D>H9=1B98[email protected]4945>71AF1<[email protected]>4925<1;1>7[email protected]@5>781<1>7 )1411214 &(9621=5>5=D;1>;?=@?B9B93181H1@DC98H1>7499>C57A1B9;1>45>71>65>?=5>1F1A>1 [email protected]9>9[email protected];1>C9C9;1F1<;1:91>;8DBDBC5>C1>73181H1H1>7=5>:14941B1A21799B9;1=?45A> (9621C5AC1A9;=5<1;D;1>@5>7D:91>=5>77D>1;1>@A9B=141>;131 $5C9;13181H1491A18;1>@141@A9B=13181H1@DC98[email protected]=5=D>3D<;1>21>H1;F1A>1[email protected]E9?<5C9>497?29AD89:1D;D>9>7?A1>H541>=5A18 (9621:D7121>H1;=5<1;D;1>5;[email protected]=5>491<1=45>71>=5491[email protected]=9>H1;19A41>75<5=2D>7B12D> 5A41B1A;1>!(%(/700(03(/$-$4,.215(3$+$:$'$136,.$.(4-$.$1/$+52$/52$/%(4,.76'$/$0%7.7/$6,+$1Tes Kompetensi Awal @1@5A25411>1>C1A121H1>71>=1H141>21H1>71>>H1C1 1719=1>1B961C21H1>71>@14135A=9> @1H1>749=1;BD445>71>@5=291B1>9>45;B291BA5<1C9641>9>45;B291B=DC<1; 1719=1>1B961C<5>B135=2D>741><5>B135;D>7C5A8141@25A;1B3181H1H1>7=5<5F1C9>H1 ,52DC;1>[email protected]=1>611C<5>B1H1>7>41;5C18D9 To k o hSeorang fisikawan Belanda,Christian Huygens dilahirkan diDen Haag, pada 14 April 1626.Ayahnya seorang diplomat dansastrawan. Pada 1666, iamemberikan sumbangan pentingtentang ilmu Matematika,Astronomi, Optik, dan Mekanika,yang membuat namanya terkenalsebagai ilmuwan penting di Eropa.Pada 1655, Huygens menyempurna-kan teleskopnya yang cukup kuatuntuk menemukan sebuah satelitPlanet Saturnus, kemudian diberinama Titan. Pada awal 1660-an iamenemukan lensa pelihat (okuler)yang terdiri atas gabungan lensa,guna mengurangi gangguan warnayang timbul akibat penggunaanlensa-lensa non-akromatik, lensa inimasih dipakai sampai sekarang.Christian Huygens(1580 – 1626)Sumber:Jendela Iptek, 1997

109Cahaya dan Optika@5>5<9C91>>H1(9621=5>[email protected]<;1>218F1@141D=D=>H13181H1C5A49A91C1BB5;[email protected]<1>@1AC9;5<H1>749B52DC,.-1/ )"/b.Teori Gelombang)141 7:*(1525ADB181=5<1F1>-5?A9)1AC9;5<45>71>=5>H1C1;1>218F13181H1[email protected];1>75<?=21>7H1>725A75A1;45>71>;[email protected]>C5AC5>CD41<1==549D=5C5A &5>DADC7:*(15C9C9;C9C9;@141=D;175<?=21>7H1>7=5A1=21C[email protected]491>771@B52171975<?=21>721AD )14175<?=21>7<9>7;1A1>=D;175<?=21>7>H1[email protected]<9>7;1A1>B541>7;1>@14175<?=21>741C1A=D;175<?=21>7>H1[email protected]71A9B<DADB -5?A975<?=21>7[email protected]=5H1;9>;1>218F1<1:D3181H141<1=19A<5298<1=21C[email protected]49D41A1 5>71>45=9;91>=5>DADC7:*(15-5?A9)1AC9;5<(96217D7DA 01<[email protected]>45=9;91>C5?A975<?=21>7C941;[email protected]=5>:5<1B;1>C5>C1>7@5A1=21C1>3181H1[email protected]71A9B<DADB $5<5=181>9>9H1>7=5>H5212;1>(9621C941;B5CD:D45>71>C5?A975<?=21>7 -5?A97:*(15[email protected]=5>5=D;1>AD=DBAD=DB@5=291B1>41>@5=1>CD<1>3181H145>71>B1>71C=5=D1B;1> B. Pemantulan Cahaya121>79<=D@5>75C18D1>C5>C1>73181H1H1>7[email protected]<1:1A9B961CB961C@5A1=21C1>3181H1[email protected]@5=1>CD<1>@5=291B1>B5AC1@A9>B9@:1<1>>H1B9>1AB9>1A49B52DC,-0&( $",*"0.&1<1=[email protected];175?=5CA93181H1[email protected]4971=21A;1>45>71>B9>1A[email protected]71A9BH1>7C571;<DADB45>71>=D;175<?=21>741>C941;[email protected]>D8>H1[email protected]>7;1>B961C75<?=21>741A93181H1C5AB52DC )5>771=21A1>3181H1B521719B9>1A[email protected]71A9B<DADBC941;[email protected]49C5A1@;1>41<1=,-0&( #&/&/)141[email protected];169B9B3181H181ADB[email protected]>D8>H1[email protected]>41>7B52171975<?=21>7;1A5>1565;565;9>C5A65A5>B941>496A1;B9>H1B1>71C4?=9>1> 1.Pemantulan Baur dan Pemantulan Teratur)141D=D=>H1B5C91@@5=D;11>25>41[email protected]=5=1>CD<;1>3181H1H1>7:1CD8@141@5A=D;11>25>41C5AB52DC )5A=D;11>25>41[email protected][email protected]@5A=D;11>;1B1A1C1D81<DB ,525A;1B3181H1H1>7:1CD8@14125>4145>71>@5A=D;11>;1B1A1;1>[email protected]>CD<;1>45>71>1A18B9>1A@1>CD<H1>7C1;C5A1CDA )5=1>CD<1>9>949B52DC-"*+01)+ 1.@5A81C9;1>$0%$4 [email protected]>B525A;1B3181H1H1>7:1CD8@141@5A=D;11>81<DB1;1>[email protected]>CD<;1>45>71>1A18H1>7C5A1CDA )5=1>CD<1>9>949B52DC-"*+01)+0".01.@5A81C9;1>$0%$4 )5=1>CD<1>3181H1@141@5A=D;11>25>41C941;B5=21A1>7=5<19>;1>=5=9<9;9;5C5A1CDA1>B5BD1945>71>8D;D=8D;D=@5=1>CD<1> Tes Kompetensi Subbab A(4-$.$1/$+'$/$0%7.7/$6,+$1 &5>DADCC5?A9@1AC9;5<41>C5?A975<?=21>7[email protected];183181H19CD(9621[email protected]>[email protected]218F13181H1[email protected];1>@1AC9;5< 5A9;1>@5>:5<1B1>=5>75>19C5?A99>945>71>;1<9=1C>41B5>49A9 1719=1>189@?C5B9B7:*(15B589>77149125A@5>[email protected]218F13181H1[email protected];1>75<?=21>7 @1;5<5=181>C5?A975<?=21>7H1>7=5=2D1C(9621=1B98C941;B5CD:D45>71>C5?A99CD &5>DADC>41491>C1A1C5?A9@1AC9;5<41>C5?A975<?=21>7=1>1;18H1>7@1<9>725>1AKata Kunci•partikel•gelombangGambar 6.2Pemantulan teraturGambar 6.1Pemantulan baur

110Mudah dan Aktif Belajar Fisika untuk Kelas XAktivitas Fisika 6.1kartonsinarpantulsinar datangpointerinframerah2.Hukum Pemantulan#9;1@141.6,8,6$5,5,.$ @A?B5B@5=1>CD<1>@14135A=9>41C1A49<1;D;1>B531A1219;>41[email protected]=5>5=D;1>;[email protected]<1>218F11 BD4DC41C1>7B1=145>71>BD4DC@1>CD<2 B9>1A41C1>771A9B>?A=1<41>B9>1A@1>CD<C5A<5C1;@141B1CD2941>741C1A )5A>H1C11>49;5>1<45>71>!D;D=)5=1>CD<1> 3.Pemantulan pada Cermin5A=9>141<18@5A=D;11>H1>7[email protected]=5=1>CD<;1><529841A93181H1H1>7=5>75>19>H1 )5A=D;11>[email protected]9CD[email protected][email protected]<?71=H1>7497?B?;B589>771=5>7;9<1@1C1D;131H1>749<[email protected]<?71==9B1<>H149<[email protected]*)$* .(/Gambar 6.3Hukum Pemantulan. Sudutdatang (i) sama dengan sudutpantul (r)sinardatanggarisnormalsinarpantulirPemantulan pada Cermin DatarTujuan PercobaanMengamati pemantulan pada cermin datar.Alat-Alat PercobaanSediakanlah sumber cahaya, cermin datar, penggaris, alat tulis, dan selembar karton.Langkah-Langkah Percobaan1.Letakkan sumber cahaya, cermindatar, dan karton, seperti pada gambarberikut.2.Buatlah garis normal pada permuka-an cermin datar, titik di mana sinarakan dipantulkan (garis normaltegak lurus terhadap permukaancermin datar).3.Gambarkan sinar yang jatuh pada permukaan cermin. Sinar ini disebut sinardatang. Gambarkan pula sinar yang meninggalkan permukaan cermin. Sinarini disebut sinar pantul.4.Ukurlah sudut antara sinar datang dan garis normal. Sudut ini disebut sudutdatang. Ukur juga sudut antara sinar pantul dan garis normal. Sudut inidisebut sudut pantul. Lakukan kegiatan ini tidak kurang dari lima kali.5.Apa yang dapat Anda simpulkan dari kegiatan ini?AOPr 'r1i1Br40°ND12D1835A=9>49BDBD>[email protected]@14171=21A25A9;DC #9;1B9>1A41C1>7@14135A=9>=5=9<9;9BD4DC41C1>7JC5>CD;1>1A18B9>1A@1>CD<BD4DC@1>CD<?<5835A=9> $9$%9C9C9;&141<18BD4DC41C1>7J 5A41B1A;1>8D;D=@5=1>CD<1>&.=1;1. J PBAONAO6.JLJJ5B1ABD4DC.[email protected]4931A941A9’rPAOB J’rJJ J’r JLJLJJ5B1ABD4DC&[email protected]4931A941A9’r1iJ1iJL’rJLJJ1i[email protected];1>BD4DC41C1>7C5A8141@35A=9>Contoh 6.15B1ABD4DC&[email protected]4931A941A9

111Cahaya dan OptikaACBB'Ds0s'bendabayangan5A41B1A;1>8D;D=@5=1>CD<1>49C9C9;25A<1;D1i1r1rJ#1491A18B9>1A@1>CD<?<5835A=9>=5=25>CD;BD4DCJC5A8141@71A9B>?A=1< a.Pemantulan pada Cermin Datar@1H1>7>41<981C@14135A=9>41C1A;5C9;1>4125A49A949[email protected]>35A=9>41C1AC5AB52DC)14135A=9>C5A<981C14121H1>71>>41 1719=1>1B961C21H1>71>H1>7C5A25>CD;@14135A=9>41C1A)5A81C9;1>$0%$4 -9C9;,[email protected];1>21H1>71>41A9C9C9;, 41@D>@A?B5B@5=25>CD;1>21H1>71>@14135A=9>41C1A141<18B52171925A9;DC ,9>1A41C1>7,)B9>1A :1CD8@14135A=9>41C1A45>71>BD4DC41C1>71;5=D491>B9>1A9>9[email protected]>CD<;1> )5A81C9;1>:1<1>B9>1A ,9>1A41C1>7,)B9>1A :1CD8@14135A=9>45>71>BD4DC41C1>72;5=D491>B9>1A9>9[email protected]>CD<;1> )5A81C9;1>:1<1>B9>1A )[email protected]>:1>71>B9>1A@1>CD< 41>B9>1A@1>CD< 4925<1;1>735A=9>49<D;9B;1>45>71>71A9B[email protected]@DCDB41>25A@?C?>71>49C9C9;#149<5C1;21H1>71>C9C9;141<18H1>74925>CD;41A9@5A@?C?>71>@[email protected]>:1>71>4D1B9>1A@1>CD< 5>71>31A1H1>7B1=121H1>71>25>414D149=5>B941>C97149=5>B9[email protected]C5A25>CD;?<5835A=9>41C1A )A?B5B@5=25>CD;1>21H1>71>>H1B1=1[email protected]@14125>41C9C9; !1<H1>7[email protected]>C9>7141<1841<1=B5C91@@A?B5B@5=25>CD;1>21H1>71>8D;D=@5=1>CD<1>B5<1<D25A<1;D )5A81C9;1>$0%$4 25A9;DC .>CD;25>41H1>72D;1>[email protected]C9C9;1C1D71A9B>411;1>=5>41@1C;1>218F1D;DA1>21H1>71>25>41@5AB9BB1=145>71>D;DA1>25>41>H1 5>4141>21H1>71>81>H125A254141<1=81<1A18;9A941>;1>1>>H1 )5A81C9;1>$0%$4 1791>;9A925>41=5>:14921791>;1>1>21H1>71>41>B521<9;>H1 )5A9BC9F19>949B52DC@5=21<9;1>B9B9)0".)&+2"./&,+(<58;1A5>1141>H1@5=21<9;1>B9B99>9CD<9B1>H1>785>41;492131=5<1<D935A=9>@5>D<9B1>8DAD6>H181ADB4921<9; 5A41B1A;1>21H1>71>25>41@14135A=9>41C1A[email protected][email protected]<;1>218F1B961C21H1>71>25>41H1>74925>CD;?<5835A=9>41C1A141<18B52171925A9;DCK=1H1K D;DA1>B1=125B1A45>71>D;DA1>25>41KC571;K :1A1;25>41C5A8141@35A=9>B1=145>71>:1A1;21H1>71>C5A8141@35A=9> Gambar 6.5Ukuran benda persis sama denganukuran bayanganGambar 6.4Pembentukan bayangan padacermin datarbayanganS'SP1P2benda12Gambar 6.6Ketika bercermin, posisi kiri bendamenjadi posisi kanan bayanganmatapengamat

112Mudah dan Aktif Belajar Fisika untuk Kelas X(<58;1A5>1B9>1A@1>CD<B1=145>71>B9>1A41C1>7=1;1 #149D>CD;[email protected]=5<981C21H1>71>B5<DAD8CD2D8[email protected]<D;1>@1>:1>735A=9>41C1A=9>9=1<41A9C9>779CD2D8B5B5?A1>7 $:$1*$11:$6$'$1%$:$1*$10$:$1H1>71>>H1C1141<1821H1>71>H1>7C5A25>CD;41A9@5A@?C?>71><1>7BD>7B9>1AB9>1A3181H1B541>7;1>21H1>71>=1H1141<1821H1>71>H1>74981B9<;1>41A9@5A@?C?>71>@5[email protected]>:1>71>B9>1AB9>1A3181H1 ,5217193?>C?821H1>71>H1>74981B9<;1>@14135A=9>41C1A[email protected];1>21H1>71>=1H1;1A5>121H1>71>C5AB52DC[email protected];1>@5A@?C?>71><1>7BD>741A9@[email protected]>:1>71>B9>1AB9>1A3181H1 [email protected]>3?>C?821H1>71>>H1C1C5A:149@14121H1>71>H1>74981B9<;1>?<58@A?H5;C?A@141<1H1A !9CD>7@1>:1>7=9>9=D=BD1CD35A=9>H1>7492DCD8;1>171AB5?A1>7@5>1A9141C[email protected]=5<981CB5<DAD8CD2D8>H1H1>7C9>779>H1%=5C5A $9$%)5A81C9;1>71=21A25A9;DC 70/$+%$:$1*$12/(+'7$%7$+&(40,1'$6$4)5A81C9;1>$0%$4 :9;1B52D1825>4125A14149[email protected]>4D12D1835A=9>H1>7=5=25>CD;BD4DCB1CDB1=1<19>1;1>C5A25>CD;B5:D=<1821H1>71> #D=<1821H1>71>25A71>CD>7@141[email protected]25B1ABD4DC 5A41B1A;1>81B9<5;[email protected]=5>:D=<1821H1>71>H1>74925>CD;?<584D12D1835A=9>H1>7=5=25>CD;BD4DC141<18B52171925A9;DC ,52D1825>41C5A<5C1;49[email protected]> 2D1835A=9>41C1AH1>7=5=25>CD;BD4DCJ !9CD>7:D=<1821H1>71>H1>7C5A25>CD; $9$%9;5C18D9J+3601+ JL J+L #149 :D=<1821H1>71>H1>7C5A25>CD;2D18 JL +$5C5A1>71>+ :D=<1821H1>71>BD4DC1>C1A14D12D1835A=9>L Contoh 6.3GFHEADCBcerminGambar 6.7Benda yang diletakkan di antara duabuah cermin datar dan membentuksudut 90° akan menghasilkan 3 buahbayangan.cermin IcerminIIbayanganbayanganbayanganbendaContoh 6.2

113Cahaya dan OptikaGambar 6.8Bagian-bagian cermin cekungf = jarak fokusR = kelengkungan cerminRfOBFPa)b)c)PFOGambar 6.9Sinar istimewa pada cermincekungGambar 6.10Pembentukan bayangan di ruang IIIAB pada cermin cekungOB'FPA'ABIIIIII5A41B1A;1>$0%$4 $0%$4 41>$0%$4 [email protected][email protected]<;1>218F11 :9;125>41@141AD1>7"=1;121H1>71>H1>74981B9<;1>141<18=1H1C571;41>[email protected]2 :9;125>4125A14149AD1>7""=1;121H1>71>H1>74981B9<;1>141<18>H1C149AD1>7"""C5A21<9;41>[email protected]3 :9;125>4125A141@141AD1>7"""=1;121H1>71>H1>74981B9<;1>141<18>H1C149AD1>7""C5A21<9;41>[email protected] Gambar 6.11Gambar bayangan jika letak bendanya diruang IIGambar 6.12Gambar bayangan jika bendanya diruang IOAPA'B'BIIIIIIFOFAPA'B'BIIIIIIS'Sb.Pemantulan pada Cermin Cekung5A=9>35;D>7141<1835A=9>H1>7=5=9<9;9@5A=D;11>35;D>7 5A=9>35;D>725AB961C;?>E5A75>H19CD25AB961C=5>[email protected]<;1>B9>1A 1791>21791>35A=9>35;D>7[email protected];[email protected]@141$0%$4 (0%(167.$1%$:$1*$12/(+&(40,1&(.71*%5C1;41>B961C21H1>71>H1>74925>CD;?<5835A=9>35;D>725A71>CD>7@141<5C1;25>41 ,52D1825>41H1>749<5C1;;1>49[email protected]>B52D1835A=9>35;D>71;1>=5=9<9;921H1>71>45>71>B961CB961CC5AC5>CD )5A81C9;1>$0%$4 B961CB961C35A=9>35;D>7491>C1A1>H11 ,9>1A41C1>7H1>7B5:1:1ABD=2DDC1=1[email protected]>CD<;1>=5<1<D9C9C9;6?;DBDC1=1 2 ,9>1A41C1>7H1>7=5<1<D9C9C9;6?;DBDC1=1[email protected]>CD<;1>B5:1:1A45>71>BD=2DDC1=1 3 ,9>1A41C1>7H1>7=5<1<D9C9C9;@DB1C;5<5>7;D>71>35A=9>1;1>[email protected]>CD<;1>;5=21<9=5<1<D9<9>C1B1>H1>7B1=1 1H1>71>B52D1825>41?<5835A=9>35;D>7[email protected]49C5>CD;1>45>71>31A1=5>771=21A;1> 41A9B9>1A9BC9=5F1@14135A=9>35;D>7 1A1=5<D;9B21H1>71>25>41?<5835A=9>35;D>7141<18B52171925A9;DC )5A81C9;1>$0%$4 +$(% -".0*35A=9>35;D>74971=21A<5>7;1@45>71>21791>21791>>H1 +$(% ("!171A9B4971=21AD>CD;=5<1=21>7;1>C9>77925>41 [email protected]>71A9BC941;@5A<DC5A<1<DC9>779 +$(% ("0&$71=21A;1>B9>1A9BC9=5F1L +$(% (""*-071=21A;1>B9>1A9BC9=5F1L +$(% (")&*C9C9;H1>7[email protected];1>@5A@?C?>71>1>C1A1B9>1A@1>CD<L 41>B9>1A@1>CD<L 4925A9>1=1-9C9;9>9[email protected];1>21H1>71>41A9C9C9;$5=D491>71A9BC571;<DADBBD=2DDC1=149C1A9;41A9C9C9;;51A18BD=2DDC1=1 -9C9;9>94925A9>1=1H1>7[email protected];1>21H1>71>41A9C9C9;B589>771[email protected];1>21H1>71>41A971A9B

114Mudah dan Aktif Belajar Fisika untuk Kelas X 7%71*$1$16$4$-$4$.)2.75'$1-$4,-$4,.(/(1*.71*$1&(40,1!D2D>71>1>C1A1:1A1;6?;DB41>:1A9:1A9;5<5>7;D>71>35A=9>[email protected]4931A945>71>@5AC?<?>71>$0%$4 )14171=21AC5AB52DC[email protected];218F1B9>1AB5:1:1ABD=2DDC1=141C1>7;5@5A=D;11>35A=9>35;D>7;5=D491>[email protected]>CD<;1>=5<1<D9C9C9;6?;DB ,9>1AB9>1A9>9=5>79;DC98D;D=@5=1>CD<1>H19CDBD4DC41C1>7B1=145>71>BD4DC@1>CD< (<58;1A5>19CDB579C971[email protected];1>B579C971B1=1;1;9B9B9 B9B9#9;1B9>1A41C1>745;1CB5;1<945>71>BD=2DDC1=1[email protected]491>771@B1=145>71>B589>771 1A9B9>9[email protected]?<58218F1 #1C1D# $5C5A1>71>#:1A1;6?;DB :1A9:1A9;5<5>7;D>71>35A=9> 70753$'$&(40,1&(.71*,5<19>B531A175?=5CA9<5C1;41>B961C21H1>71>25>41[email protected]49C5>CD;1>B531A1@5A89CD>71>45>71>@5AB1=11>B52171925A9;DC )5A81C9;1>$0%$4 )141$0%$4 [email protected];218F141>B521>7D>B589>771 (<58;1A5>1# =1;1 LL’’hshsL)141$0%$4 [email protected];218F141>B521>7D> .>CD;25A<1;DC1>% / 6 .>CD;25A<1;DC1>% 6 /B589>771%%%6//6 6/ % /6(<58;1A5>1% /%/=1;1/ 6 ///6/ / 6 / 6 /// 6 / / 6 //// / /////////L Gambar 6.14Letak dan sifat bayangan benda padacermin cekungGambar 6.13Hubungan antara fokus dan jari-jari cermin cekungPRFRfAO)))Keterangan:s= jarak benda ke cerminh= tinggi bendaf=jarak fokush' = tinggi bayangans'= jarak bayangan ke cermin5>71>=5>77D>1;1>@5AB1=11>35A=9>C5AB52DC>41[email protected]=5>5>CD;1>:1A1;21H1>71>B52D1825>41 [email protected]>@5A25B1A1>21H1>71>Konvensi tanda untuk pemantulan:Ks bernilai + jika objek berada didepan cermin (objek maya)bernilai – jika objek di belakangcermin (objek nyata)Ks’ bernilai + jika objek berada didepan cermin (objek nyata)bernilai – jika objek berada dibelakang cermin (objek maya)Kr, f bernilai + jika pusatkelengkungan berada di depancermin (cermin cekung)bernilai – jika pusat kelengkunganberada di belakang cermin(cermin cembung).IngatlahBAPEDFOfs'Rsh'h

115Cahaya dan Optika494569>9B9;1>B521719@5A21>49>71>1>C1A125B1AC9>77921H1>71>41>25B1AC9>77925>41 ,531A1=1C5=1C9B[email protected]49CD<9B/ % /%Lc.Pemantulan pada Cermin Cembung5A=9>35=2D>7141<1835A=9>H1>7=5=9<9;9@5A=D;11>35=2D>7 5A=9>35=2D>725AB961C49E5A75>H19CD25AB961C=5=1>31A;1>B9>1A 1791>21791>35A=9>35=2D>7[email protected]@141$0%$4 (0%(167.$1%$:$1*$12/(+&(40,1&(0%71*,52D1825>41H1>749<5C1;;1>49[email protected]>B52D1835A=9>35=2D>7=5=9<9;921H1>71>45>71>B961CB961CC5AC5>CD 1H1>71>B52D1825>41?<5835A=9>35=2D>7[email protected]49C5>CD;1>45>71>31A1=5>771=21A;1> 41A9B9>1A9BC9=5F1@14135A=9>35=2D>7 )5A81C9;1>$0%$4 )141$0%$4 C5A<981C1 B9>1A41C1>7H1>7B5:1:1ABD=2DDC1=1[email protected]>CD<;1>B51;1>1;1>41C1>741A9C9C9;6?;DB2 B9>1A41C1>7H1>7=5>D:DC9C9;6?;DB[email protected]>CD<;1>B5:1:1A45>71>BD=2DDC1=13 B9>1A41C1>7H1>7=5>D:DC9C9;@DB1C;5<5>7;D>71>35A=9>[email protected]>CD<;1>;5=21<9=5<1<D9<9>C1B1>H1>7B1=1 1A1=5<D;9B21H1>71>25>41?<5835A=9>35=2D>7C5A<981C[email protected]9@141$0%$4 )14131A1C5AB52DCB9>1A9BC9=5F1H1>7497D>1;1>141<18B9>1A 41>B9>1A 5A41B1A;1>71=21A21H1>71>C5AB52DC[email protected][email protected]<;1>218F125>41H1>749<5C1;;1>49[email protected]>B52D1835A=9>35=2D>7B5<1<D=5>781B9<;1>21H1>71>=1H1C571;41>[email protected];539< 70753$'$&(40,1&(0%71*+D=DB@14135A=9>35=2D>7B1=1[email protected]AD=DBH1>725A<1;D@14135A=9>35;D>7H19CD L# % / %/Gambar 6.15Bagian-bagian cermin cembungR= jari-jari kelengkungan cerminP= titik pusat kelengkungan cerminF= titik fokus cerminf= jarak titik fokus ke cerminSUOfFPROFPGambar 6.17Lukisan pembentukan bayangan olehcermin cembungabcOFPGambar 6.16Sinar-sinar istimewa pada cermincembung!1<81<H1>7@5A<D[email protected];1>141<181 C1>41:1A1;6?;DB@14135A=9>35=2D>7B5<1<D25A>9<19>571C96 !1<9>949B5212;1><5C1;C9C9;6?;DB@14135A=9>35=2D>7C5A<5C1;4925<1;1>735A=9>2 D>CD;25>41>H1C149[email protected]>35A=9>35=2D>7B5<1<DC5A25>CD;21H1>71>=1H1 #149>9<19/@14135A=9>35=2D>725AC1>41>571C96 ,52D1835A=9>35;D>7=5=9<9;9:1A9:1A9;5<5>7;D>71> = ,52D1825>4149<5C1;;1>@141:1A1; =41A935A=9>C9>77925>413= !9CD>7<18<5C1;C9>77941>@5A25B1A1>21H1>71> $9$%9;5C18D9Contoh 6.42 D>CD;25>41>H1C149[email protected]>35A=9>35=2D>7B5<1<DC5A25>CD;21H1>71>=1H1 #149>9<19B@14135A=9>35=2D>725AC1>41>571C96

116Mudah dan Aktif Belajar Fisika untuk Kelas Xp'ss'pbendabayanganP/ = = # =%3=5>71>=5>77D>1;1>(45$0$$1 ;[email protected]?<58// # /L / L///= / %%% /%%%% % 3= 3=#149<5C1;21H1>71>=49[email protected]>35A=9>C9>779>H1 3=41>@5A25B1A1>>H1 ;1<9 ,52D1825>4149<5C1;;1>3=49[email protected]>35A=9>35=2D>7H1>725A:1A9:1A93= 1 9=1>1<5C1;21H1>71>2 [email protected]@5A25B1A1>>H13 %D;9B:1<1>>H1B9>1A@141@5=25>CD;1>21H1>71> $9$%9;5C18D9/3=L3= #LL 3=1 6//L /L / L//L 3=2 L // #149@5A25B1A1>>H1;1<9B961C21H1>71>C571;=1H141>[email protected];539<3 Contoh 6.5Kata Kunci•optika geometri•optika fisis•pemantulan baur•pemantulan halus•bayangan nyata•bayangan maya•titik fokus utama•pusat kelengkunganTes Kompetensi Subbab B(4-$.$1/$+'$/$0%7.7/$6,+$1 ,525A;1BB9>1A41C1>7:1CD8@141B52D18@5A=D;11>35A=9>45>71>BD4DCJ #9;1499>79>;1>B9>1A@1>CD<?<5835A=9>;54D1B5:1:1A45>71>B9>1A41C1>7[email protected];18BD4DC1>C1A135A=9>@5AC1=141>35A=9>;54D1 -9712D1835A=9>49BDBD>[email protected]71=21A25A9;DC -5>CD;1>1A18B9>1A@1>CD<41A935A=9>C5AB52DC D12D1835A=9>41C1A=5=25>CD;BD4DCJ ,52D1825>41C5A<5C1;49[email protected]>;54D135A=9>C5AB52DC -5>CD;1>:D=<1821H1>71>H1>7C5A25>CD; ,52D1825>41C571;C9>779>H1 3=49<5C1;;1>49[email protected]>35A=9>35;D>725A:1A9:1A9 3=@141:1A1;3=41A935A=9> 1 -5>CD;1>:1A1;21H1>71>;535A=9> 2 %D;9B:1A1;>H1B9>1A@141@5=25>CD;1>21H1>71> 3 -5>CD;1>B961CB961C21H1>71> 30°140°120°cermin Icermin IIcermin III

117Cahaya dan OptikaC. Pembiasan Cahaya71A>41=5=181=9@5A9BC9F1@5=291B1>3181H1<1;D;1><18;5791C1>25A9;DC )5A81C9;1>>H1<1<[email protected]B5>C5A[email protected]@141.6,8,6$5 %9>7;D>71>H1>7=5<9>7;[email protected]69<1=5><[email protected]141<18[email protected]D41A1;5=D491>3181H149C5ADB;1>;5D41A1<D1A D;1>;183181H1>H1=5>H521A@1@5A1>;131@5=21C1BH1>7=5=25>CD;2?<1)5A9BC9F1H1>7491<1=93181H149>1=1;1>@5A9BC9F1@5=291B1> "*&/+."#.(/&141<18-".&/0&3 -"*"),(+ .% %4 ("0&(*")"30&&!+$0/+0.!1*"!&1*4+$"."! )5=291B1>3181H1C5A:1491;921C;[email protected]>3181H125A2541@141B5C91@=549D= &D>7;9>>41@5A>18=5<981CB52D18@5>B9<H1>7C5A35<D@B521791>;541<1=19A4941<1=75<1B@5A9BC9F19CD[email protected]<981C;1>@5=291B1> )5A81C9;1>$0%$4 1791>@5>B9<H1>7C5A35<D@;519A;5<981C1>@1C18 )5A81C9;1>@D<1:9;149<9>7;D>71>>41[email protected];?<1=H1>7:5A>9841B1A;?<1=C5AB52DCC5A<981C<529841>7;1< )5A9BC9F1C5AB52DC:D71[email protected];1>3?>C?8@5A9BC9F1@5=291B1>3181H1 Aktivitas Fisika 6.2Pembiasan dan PemantulanTujuan PercobaanMengamati peristiwa pembiasan dan pemantulan.Alat-Alat Percobaan1.Baterai kering 6.Kapas2.Pengunci kertas 7.Bohlam kecil dalam wadah3.Pensil 8.Klip kertas4.Obeng, gunting, dan double tape 9.Kabel5.Aluminium foil10.Botol air plastikLangkah-Langkah Percobaan 1.Potong bagian atas botol, kemudian menggunakan pensil lubangi botoldi pinggiran botol. 2.Rekatkan aluminium foil di dalam bagian atas botol yang sudah dipotong,seperti pada gambar (b). 3.Pasangkan dua buah kabel pada bohlam kecil yang sudah ditempatkanpada wadahnya. 4.Satukan baterai secara seri, lalu rekatkan kabel ketiga pada bagian bawahbaterai (kutub negatif ), seperti pada gambar (d). 5.Rekatkan satu kabel dari wadah bohlam ke bagian atas baterai (kutub positif ). 6.Masukkan kabel ke dalam lubang di pinggir botol, penuhi botol dengankapas dan tempatkan kedua kabel dengan pengunci kertas. 7.Tempatkan wadah bohlam di atas baterai, dan tempatkan tengah-tengahbohlam tepat di bagian atas botol yang sudah diratakan aluminium foil. 8.Bengkokkan klip kertas dan tempatkan pada salah satu ujung penguncikertas sehingga menjadi saklar senter tersebut. 9.Tekan ujung lainnya klip kertas ke pengunci kertas yang lain senter kini menyala.10.Apa yang menyebabkan nyala filamen lampu menyebar ke depan senter?11.Apa manfaat adanya aluminium foil pada bagian atas botol yangdipotong? Peristiwa apa yang terjadi pada aluminium foil tersebut?(a)(b)(c)(d)(e) ,52D1825>4149<5C1;;1>49[email protected]>35A=9>35=2D>7B545=9;91>[email protected]B589>77125B1A21H1>71>>H1;1<9 #9;121H1>71>H1>7C5A25>CD;[email protected]L41>:1A9:1A9;5<5>7;D>71>35A=9>35=2D>7 3=89CD>7:1A1;25>41;535A=9> Gambar 6.18Pensil seperti patah ketikatercelup ke dalam air

118Mudah dan Aktif Belajar Fisika untuk Kelas X1. Indeks Bias">45;B291B[email protected][email protected]>41>7B521719BD1CD;[email protected]>=549D==5=291B;1>=5=25<?;;1>1A18A1=21C3181H1 #9;13181H125A75A1;41A9E1;D=1C1DD41A1;5=549D=<19>9>45;B291B>H149B52DC&+!"(/ &/*10)(=549D=C5AB52DC )1415;B@5A9=5>,>5<<9DB>9<199>45;B291BH1>7[email protected]+ [email protected];1>>9<199>45;B291B=DC<1;;131;1A5>13181H125A75A1;41A9E1;D=1C1DD41A1;5;131 ,531A1=1C5=1C9B[email protected]49CD<9BB52171925A9;DC L+ 22.Hukum Pembiasan)5=291B1>3181H1C941;B5=21A1>7[email protected]=5>79;DC98D;D=8D;D=@5=291B1> !D;D=@5=291B1>@5AC1=1;1<949>H1C1;1>?<58#,//(%424'!1(//,7518<99B9;125A;521>7B11>5<1>41 !1(//,75=5<1;D;1>5;[email protected]=5>45>71>=5<5F1C;1>B525A;1BB9>1A@14121<?;;131 5A41B1A;1>81B9<5;[email protected]=5>H1>749<1;D;1>>H1!1(//,75;5=D491>=5>H1C1;1>!D;D=")5=291B1>>H1H19CD-".+!&+$+/&+1//1!10!0+$!+/&+1//1!10&/!.&/101 %44+$!0+$!.&/101*"!&1*("*"!&1*)&+*".1-(+/101(,+/0+04+$"/.+4 /* !"+$+ -".+!&+$+ &+!"(/ &/ ("!1 *"!&1* 0"./"10+9B9>&+AB9>.B9>B9>.&+&.+"$%(/ ">45;B91B&DC<1;[email protected]&549D=(',70/1;D=.41A19A JC9<1<;?8?<$131$D1AB1$5A?>1<9>C1$131@<5G9">C1> B9>B9>&.& +.L$5C5A1>71>&BD4DC41C1>7.BD4DC291BA5<1C96+9>45;B291B">45;B291BA5<1C96BD1CD=549D=141<18@5A21>49>71>>9<199>45;B291B=DC<1;41A94D1=549D=H1>725A2541 &9B1<>H1B525A;1B3181H125A75A1;41A9=549D=19A+&.;5=549D=;131+( ,531A1=1C5=1C9B9>45;B291B19AA5<1C96C5A8141@=549D=;131[email protected]49CD<9B&.( &.( +++Sumber: Fundamentals of Physics, 2001Gambar 6.19Deskripsi hukum pembiasanriB$5C5A1>71>+9>45;B291B=DC<1;;[email protected]>3181H149E1;D= D41A12;[email protected]>3181H149BD1CD=549D='9<199>45;B291B=DC<1;[email protected]=549D=49CD>:D;;1>@141"$%(/

119Cahaya dan Optikamedium air(medium–1)medium kaca(medium–2)Gambar 6.20Sinar yang melalui dua mediumberbeda, yaitu air dan kaca.,531A1D=D=:9;13181H125A75A1;41A9=549D= ;5=549D= 9>45;B291B=549D= A5<1C96C5A8141@=549D= ,531A1=1C5=1C9B[email protected]49CD<9B;1>B52171925A9;DC +++ B9>B9>+&++.)5AB1=11>C5AB52DC[email protected]:D7149CD<9BB52171925A9;DC L 9;5C18D92 #45>71>#6A5;D5>B941>@1>:1>775<?=21>7 5>71>45=9;91>>9<199>45;B291B[email protected][email protected]?<58:D7141A9@1>:1>775<?=21>7 2121nL B9>B9>+&++.L (45$0$$1 ;41>3(45$0$$1 ; =5=9<9;9=1;>169B9BH19CD;[email protected]>3181H141<1=BD1CD=549D=25A21>49>7C5A21<9;45>71>>9<199>45;B291B>H1 &1;BD4>H1:9;19>45;B291BB5=1;9>25B1A;[email protected]>3181H1B5=1;9>;539< ,5217193?>C?8;[email protected]>3181H141<1==549D=;131<5298;539<4921>49>7;1>45>71>;[email protected]>3181H1;5C9;1=5A1=21C41<1=19A <1B1>>H19>45;B291B=DC<1;;131<529825B1A[email protected]9>45;B=DC<1;19A ,5<19>9CD>41:D71[email protected]=5>[email protected]<;1>218F1;5C9;175<?=21>7=5A1=21C41A9BD1CD=549D=;5=549D=<19>H1>79>45;B291B>H125A2541@1>:1>775<?=21>741>25B1A;[email protected]>275<?=21>7C5AB52DC25AD218>1=D>6A5;D5>B9#75<?=21>7C5AB52DCC941;25AD218 $5C5A1>71>+9>45;B291B=DC<1;=549D= +9>45;B291B=DC<1;=549D= + 9>45;B291B=549D= A5<1C96C5A8141@=549D= &BD4DC41C1>749=549D= .BD4DC291B49=549D= 3.Hubungan Cepat Rambat Cahaya dan Indeks Bias Medium)5A81C9;1>$0%$4 &9B1<>H1BD1CD75<?=21>72941>7)*49<5F1C;1>=5<1<D9=549D= ;5=549D= H1>7<5298[email protected] ,5C5<18F1;CD075<?=21>72941>7)*25A141@1412941>7,+20202020 22Gambar 6.21Pembiasan cahaya melalui duamediummedium 1medium 2))RSPQ1221

120Mudah dan Aktif Belajar Fisika untuk Kelas X1<1=B52D185;[email protected]=5>D>CD;=5>5>CD;1>;[email protected]>3181H14941<1=19AB5?A1>7B9BF1=5<5F1C;1>B525A;1B3181H1;541<1=19A45>71>BD4DC41C1>7J $5=D491>B9BF1=5>31C1CBD4DC291BH1>7C5A:1494941<1=19AC5A>H1C125B1A>H1 J #9;1;[email protected]>3181H149D41A1491>771@M = BC5>CD;1>;[email protected]>3181H14941<1=19A $9$%9;5C18D9&JM = B. J4919AB9>B9>2&rM B9> JB9>J= BM m/s= B M = B#149;[email protected]>3181H141<1=19A141<18 M = B Contoh 6.6Gambar 6.22Sinar datang dibiaskan:(a) mendekati garis normal jika n1 < n2;(b) menjauhi garis normal jika n1 > n2.in1n2rn1>n2irn1n2n1<n2,55;?A9;1>25A1414941B1A;?<1=H1>741<1=>H1=19A+[email protected][email protected];@14171=21A49[email protected]>7 )141;541<1=1>[email protected];18<5C1;9;1>41B1A;?<1=C5AB52DCC5A<981C?<58@5>71=1C41A9@5A=D;11>19A:9;11 9;1>49<981C@5>71=1CB531A1C571;<DADB2 BD4DC1>C1A1=1C141>71A9B>?A=1<B525B1AJ $9$%1 )5A81C9;1>71=21A #9;1@5>71=1C=5<981C9;1>B531A1C571;<DADB1;1>=5=5>D89@5AB1=11>C1>.B9>.41>C1>&B9>&,9>1A41C1>741A99;1>B589>771C1> B9>C1> B9>&&!..!1C1D1!&.+!+!=1;1;541<1=1>9;1>[email protected]?<58H19CD !1C1D!=#149;541<1=1>B5=D9;1>H1>749<981C@5>71=1CB531A1C571;<DADB141<18= 2 $541<1=1>9;1>D>CD;BD4DC1>C1A1=1C1@5>71=1C41>71A9B>?A=1<.J141<18B9>B9> B9>B9>1!&.+&&.+ B9>&B9>J& JB589>771C1>C1> JC1>C1>J &!!.! =#149;541<1=1>B5=D9;1>D>CD;BD4DC.J=5>:149 = Contoh 6.7dasar kolam4 mnud = 1nair = 43rd = 4 mird 'i,521719;?>B5;D5>B941A9!D;D=",>5<<9DB9>9B9>1A41C1>741A9=549D=;DA1>7[email protected];5=549D=<5298[email protected]+ +/&+.(+!&&/(+*"+!"(0&$.&/+,.*)!+'&(/&+.!0+$!.&*"!&1*)"&%.-0("*"!&1*(1.+$.-0++B9>1A1;1>49291B;1>=5>:1D8971A9B>?A=1< (4+$6,.$1$0%$4 matapengamat(a)(b)

121Cahaya dan Optika4.Sudut Kritis dan Pemantulan Sempurna&5>[email protected]25A<91>[email protected];25A;9<1D1>;5C9;13181H1:1CD8@141@5A=D;11>>H1&5>[email protected]@141B11CC5A9;=1C181A9:1<1>A1H125A1B@1<[email protected];[email protected]C5A75>1>719A)141;54D175:1<19B9;1C5AB52DC3181H1=5>71<1=9@5=1>CD<1>B531A1[email protected]>1 1719=1>1@5=1>CD<1>[email protected]>1[email protected]C5A:149)5A81C9;1>$0%$4 1=21AC5AB52DC=5>D>:D;;1>3181H125A75A1;41A9=549D=<5298[email protected];131;5=549D=;DA1>7[email protected]D41A11C1D41A9=549D=25A9>45;B291B<529825B1A;5=549D=25A9>45;B291B<5298;539<B589>771B9>1A291B>H1=5>:1D8971A9B>?A=1< $5C9;1BD4DC41C1>7>?<BD4DC291B>H1:D71>?<[email protected]49CD>:D;;1>?<58B9>1A $5=D491>@141B11CBD4DC41C1>7[email protected]B9>1A B9>1A41>B9>1ABD4DC291B@D>25AC1=21825B1A1C1DB5=1;9>=5>:1D8971A9B>?A=1< )141B11C25B1ABD4DC41C1>7C5AC5>CDH1;>9[email protected]B9>1A3181H149291B;1>JC5A8141@71A9B>?A=1<B589>771B9>1A291B>H1B5:1:1A45>71>@5A=D;11>2941>721C1B=549D=;131D41A1 )141;51411>[email protected]9>9BD4DC41C1>749B52DCBD4DC;A9C9B 5>71>;1C1<19>BD4DC;A9C9B141<18BD4DC41C1>7;5C9;1B9>1A41C1>749291B;1>B525B1AJ #9;1BD4DC41C1>7[email protected]<179=5<52989BD4DC;A9C9B3181H1C941;1;1>49291B;1>=5<19>;1>[email protected]>CD<;1>B531A1[email protected]>1 AC9>H13181H1C941;1;1>;5<D1A41A9=549D=;131[email protected]49CD>:D;;1>?<58B9>1A )5A9BC9F19>9<18H1>749B52DC@5=1>CD<1>[email protected]>15A41B1A;1>81<C5AB52DC[email protected][email protected]<;1>218F1@5=1>CD<1>B[email protected]>181>H1C5A:149:9;1=5=5>D894D1BH1A1C25A9;DC 1 181H141C1>741A9=549D=<5298[email protected];5=549D=;DA1>7[email protected] 2 ,D4DC41C1>7<529825B1A[email protected]BD4DC;A9C9B Gambar 6.23Deskripsi geometri tentang sudut kritisdan pemantulan sempurnan2n1(n1>n2)123456iudarakacaiiirrrrirAktivitas Fisika 6.3Sepotong plastik transparanterapung dipermukaan air. Agarsinar datang seperti pada gambardi atas dipantulkan sempurna olehpermukaan batas plastik air. Jikaindek bias plastik nk dan indek biasair na, berapa besar sudut?Tantanganuntuk AndaudaraairplastikPemantulan SempurnaTujuan PercobaanMengamati pemantulan sempurna.Alat-Alat PercobaanGelas minum, lilin, dan air.Langkah-Langkah Percobaan1.Isilah gelas minum dengan air sampai hampir penuh.2.Letakkan gelas tersebut di pinggir meja.3.Nyalakan lilin pendek dan letakkan dekatdengan gelas.4.Perhatikan gambar berikut.Amati dari arah yang berseberangandengan lilin dari arah agak dibawah permukaan.5.Apa yang dapat Anda amati?6.Apa kesimpulan Anda dari kegiatan ini?)A9>B9@@5=1>CD<1>B[email protected]>149=1>611C;1>41<1=C5;>?<?79;?=D>9;1B9H1;>9@141B5A1C[email protected];#&". ,-0& [email protected]@141$0%$4 ,5A1C[email protected];141<18BD1CDB5A1C81<DBC5A2D1C41A9@<1BC9;1C1D;131H1>7497D>1;1>D>CD;=5>H1<DA;1>3181H11C1D75<?=21>75<5;CA?=17>5C9; ,5A1C[email protected];C5A49A91C1B21791>9>C941>21791><D1AB521719@5=2D>7;DB>H1 1791>9>C9C5A2D1C41A9;131H1>7=5=9<9;99>45;B291BC9>77941>25A;D1<9C1B219; matapengamat

122Mudah dan Aktif Belajar Fisika untuk Kelas XGambar 6.24(a) Pemantulan sempurnapada serat optik.(b) serat optik.(a)(b)Contoh 6.8!9CD>7BD4DC;A9C9B25A<91>H1>7=5=9<9;99>45;B291B=DC<1; @141B11C49<5C1;;1>49D41A1 $9$%9;5C18D9+ + B9>(+& + &; J#149BD4DC;A9C9B25A<91>141<18 J B9>B9>(&+5+1C1DB9>(+& +L $5C5A1>71>&;BD4DC;A9C9B(11sintir5Pembiasan pada Kaca Plan Paralel$131@<1>@1A1<5<141<18B5;[email protected]>7;131H1>7;54D1B9B9@1>:1>7>H1492D1CB5:1:1A $131@<1>@1A1<5<[email protected]497D>1;1>D>CD;=5>71=1C9:1<1>>H1B9>1AH1>7=5>71<1=9@5=291B1>41>D>CD;=5>5>CD;1>9>45;B291B;131C5AB52DC ,9>1A41C1>741A9D41A1=5<5F1<9;131B5C521<!3=;5=D491>=5>D:D=549D=D41A1;5=21<9 )141@A?B5BC5AB52DC[email protected][email protected];@141$0%$4 41>$0%$4 59>1A=5>71<1=9@5A75B5A1>41A91A18B9>1AB5=D<1 5B1A>H1@5A75B5A1>B9>1AC5AB52DC[email protected]4989CD>7B52171925A9;DC )5A81C9;1>(B9>( (0&6. L ">45;B291BH1>7C9>7791;1>=5>71;921C;1>BD4DC;A9C9B;539<B589>771B9>1A41C1>745>71>BD4DC41C1>7H1>7C941;C5A<1<D25B1A1;1>=5>71<1=9@5=1>CD<1>[email protected]>1 1791><D1AH1>7[email protected];1>@5=2D>7;DBC5A2D1C41A9@<1BC9;1C1D=1C5A91<<19>H1>725A6D>7B9=5<9>4D>7921791>9>C9 (<58;1A5>13181H11C1D75<?=21>75<5;CA?=17>5C9;H1>7=1BD;;541<1=B5A1C[email protected];=5>71<1=9@5=1>CD<1>[email protected]>1@141B11C;5<D1A41A9B5A1C[email protected];5>5A793181H1C941;21>H1;H1>789<1>7 5A41B1A;1>81<9CD:9;1H1>749;9A9=141<18B9>H1<B9>H1<;?=D>9;1B941<1=25>CD;75<?=21>73181H1@141B11C49C5A9=149C5[email protected]CD:D1>B9>H1<C5AB52DC[email protected]B531A1DCD8C1>@121>H1;;589<1>71>5>5A79 5A41B1A;1>@141@A?B5BC5A:149>H1@5=1>CD<1>[email protected]>1[email protected]49C5>CD;1>@D<125B1A>H1BD4DC;A9C9BD>CD;4D1=549D=C5AC5>CDB52171925A9;DC )141B11CC5A:149@5=1>CD<1>[email protected]>125A<1;D@5AB1=11>25A9;DC Gambar 6.25Seberkas cahaya memasukikaca plan paraleldDBAOtr2r1i1Gambar 6.26Pergeseran arah sinarpada kaca plan paralelB9>B9>+&.+45>71>++41>.JB589>771

123Cahaya dan Optika(1cosdrL 5A41B1A;1>([email protected]?<58(3?B ( (!.5A41B1A;1>(45$0$$1 ;41>(45$0$$1 ; [email protected]?<583?B B9>!0.&6.B589>77125B1A@5A75B5A1>B9>1A0B9> L3?B!&..L $5C5A1>71>&BD4DC41C1>7!C521<;131@<1>@1A1<5<.BD4DC291B 025B1A@5A75B5A1>B9>1A,525A;1BB9>1A<1B5A:1CD8@141@5A=D;11>;131@<1>@1A1<5<[email protected]=5=25>CD;BD4DC41C1>7B525B1AJ #9;1C521<;131@<1>@1A1<5< 3=41>BD4DC291B JC5>CD;1>25B1A@5A75B5A1>H1>7491<1=9?<58B9>1A<1B5AC5AB52DC $9$%9;5C18D90J. J! 3=0B9> L3?B!&.. B9> JL J 3?B J#149;5C9;1=5<5F1C9;131@<1>@1A1<5<B9>1A<1B5A=5>71<1=9@5A75B5A1>3=41A91A18B5=D<1 Contoh 6.96.Pembiasan pada Prisma)A9B=1[email protected];1>25>41H1>7C5A2D1C41A975<1BC5=2DB3181H1CA1>B@1A1>H1>7;54D1B9B9>H14921C1B92941>7@5A=D;1>H1>7A>5=25>CD;BD4DCC5AC5>CDB1CDB1=1<19> ,D4DCC5AB52DC49>1=1;1>BD4DC@5=291BB9=2?< 941>7@5A=D;11>@A9B=125A6D>7B9B5217192941>7@5=291B )5A81C9;1>:1<1>>H1B9>1AH1>7=5<5F1C9B52D18@A9B=1@141$0%$4 181H141C1>741A9D41A1=5>D:D2941>7@5A=D;11>@A9B=11;1>49291B;1>=5>45;1C971A9B>?A=1< $5=D491>;5C9;13181H1=5>9>771<;1>@A9B=1=5>D:DD41A13181H1C5AB52DC1;1>49291B;1>=5>:1D8971A9B>?A=1< ,5C5<18=5<5F1C9@A9B=13181H1=5>71<1=945E91B9 5B1A>H1BD4DC45E91B9H1>7491<1=93181H1141<18B52171925A9;DC )5A81C9;1>$0%$4 )5A81C9;1> . 6 &41> & 6 . J 6 6 )5A81C9;1>J.1J.2Gambar 6.27Prisma segitigaGambar 6.28Jalannya sinar pada prismaNNsinardatangsinarbias)

124Mudah dan Aktif Belajar Fisika untuk Kelas X J 6 6 J JJ 66 . 66 &12riL ,D4DC45E91B9>H1 J J J6 666 &L..&& .L.& 12irL $5C5A1>71>BD4DC@5=291B@A9B=1.BD4DC291B41A9B9>1A=1BD;&BD4DC41C1>7B9>1A=1BD;.BD4DC291B41A9B9>1A;5<D1A&BD4DC41C1>7B9>1A;5<D1ABD4DC45E91B9,52D18@A9B=1C5A2D1C41A9;131+ =5=9<9;9BD4DC@5=291BJ #9;1B525A;1BB9>1A<1B5A:1CD8@141B1<18B1CD@5A=D;11>@5=291B>H145>71>BD4DC41C1>7J[email protected];18BD4DC45E91B9H1>7491<1=9?<58B9>1A<1B5AC5AB52DCB5C5<18=5<5F1C9@A9B=1$9$%9;5C18D9&J+ =549D=;131+ =549D=D41A1J,D4DC45E91B94989CD>745>71>=5>77D>1;1>@5AB1=11> 12ir(<58;1A5>1&41>C5<1849;5C18D9>9<19.BD4DC291B;54D1@5A<D4931A9C5A<5298418D<D )141@5A=D;11>@5=291B@5AC1=125A<1;D@5AB1=11>,>5<<9DB25A9;DC Contoh 6.10Gambar 6.29Penurunan rumus sudut deviasiprisma7.Deviasi Minimum,5C91@B9>1AH1>741C1>7@141@A9B=11;1>=5>71<1=945E91B9H1>7=5>781B9<;1>BD4DC45E91B9C5AC5>CD ,1<18B1CDB9>1A41C1>7C5AC5>CD@1BC91;1>=5>781B9<;1>>9<19BD4DC45E91B9=9>9=D= [email protected]>;?>49B9;8DBDBB9>B9>&+.+45>71>++D41A141>+ ;131B9> B9>B9> ... '9<19&49C5>CD;1>B52171925A9;DC 211irr260 19,47 40,53i $5=D491>>9<19.49C5>CD;1>B52171925A9;DC B9> B9>B9> B9>J+.&..+B9> 1A3B9> J...#149BD4DC45E91B9H1>7491<1=93181H1;5C9;1=5<5F1C9@A9B=1;131C5AB52DCB525B1A &.6J JLJ J PSTQr1r2i2i1RB

125Cahaya dan Optika7<7A3?8/273?2/@/?9/<6/@7:>3;0B9A7/<# "2/>/AA3?8/27>/2/@//A@B2BA2/A/<5>3?A/;/@/;/23<5/<@B2BA07/@932B/3@/?<E/@B2BA23C7/@7;7<7;B;@30B/6>?7@;/2/>/A271/?7@30/5/703?79BA':369/?3</;/9/@367<55/ K&7:/727;/@B99/<932/:/;%12!-!!. 7@367<55/23C7/@7>?7@;/;3<8/27K 3?2/@/?9/< B9B;*<3::7B@ @7<@7<K %12!-!!. 72/<%12!-!!. 7[email protected]@[email protected]/<932/:/;%12!-!!. 7@367<55/27>3?=:36 @7<@7<@7<@7<"79/9317:@7< @367<55/KK K K K*30B/6>?7@;/E/<5A3?0B/A2/?79/1/E/<5;3;7:797@B2BA>3;07/@ I27:3A/99/<2/:/;;327B;/7?"79/@303?9/@@7</?2/A/<52/?7/7? ;3;/@B97>?7@;/03?/>/9/6@B2BA23C7/@7;7<7;B;>?7@;/[email protected]!5!"793A/6B7 I ;327B;/7?;327B;9/1/K #3A3?/<5/<@B2BA23C7/@7;7<7;B;1,2n@B2BA07/@?3:/A74;327B; A3?6/2/>;327B;@B2BA23C7/@7>?7@;/Contoh 6.11

126Mudah dan Aktif Belajar Fisika untuk Kelas X8.Lensa$3<@/A3:/62793</:=?/<5@38/92/6B:B(/2//0/2>3?A3<5/6/<=?/<5=?/<5.B</<72/<?/0@B2/6;3<53</:2/<;3<55B</9/<:3<@/*//A7<7:3<@/8B5/0/<E/9275B</9/<@30/5/70/57/<BA/;//:/A/:/A@3>3?A79/;3?/A3?=>=<5;[email protected]=>>?=E39A=?2/<9/1/;/A/*3;B//:/A[email protected]@/<5/A>3<A7<52/<03?5B</2/:/;93672B>/<':369/?3</7AB;3;/6/;7@74/A@74/A>3;07/@/<>/2/:3<@/@/<5/A>3<A7<5$3<@//2/:/603<2/03<7<5E/<5270/A/@7=:362B/>3?;B9//<:3<59B<5(3?;B9//<;3:3<59B<5[email protected];3?B>/9/<0/57/<>3?;B9//<0=:/$3<@/E/<523;797/<[email protected]:3<@/@43?7@(3?;B9//<:3<@/@43?7@2/>/A03?B>/932B/<E/13;0B<5932B/<E/139B<5/A/B5/0B<5/<13;0B<52/<139B<5$3<@/@43?7@A3?27?7/A/@2B/83<7@E/7AB:3<@/13;0B<52/<:3<@/139B<5$3<@/13;0B<59=<C39@/A/B:3<@/9=<C3?53</2/:/6:3<@/E/<50/57/<A3<5/6<E/:3076A30/:2/?7>/2/0/57/<A3>7<E/$3<@/7<7[email protected]/A;3<5B;>B:9/<03?9/@@7</?!-"!1 2/>B<:3<@/139B<59=<9/4/A/B:3<@/27C3?53</2/:/6:3<@/E/<50/57/<A3<5/6<E/:3076A7>7@2/?7>/2/0/57/<A3>7<E/$3<@/7<7[email protected]/A;3<E30/?9/<03?9/@@7</?!-"!1 *303:B;:30768/B6;3;/6/;743<=;3</43<=;3</E/<5A3?8/27>/2/:3<@/<2/6/?B@;3<53A/6B70/57/<0/57/<:3<@/23<5/<0/79(/2/:3<@/A3?2/>/A>B@/A=>A79A7A794=9B@2/<>B@/A93:3<59B<5/<:3<@/!-"!1 ;3;>3?:76/A9/<@93;/@30B/6:3<@/2/<0/57/<0/57/<<E/a.Pembiasan Cahaya pada Lensa Cembung/6/E/E/<58/AB6>/2/>3?;B9//<:3<@/13;0B<5/9/<;3<5/:/;7>3;07/@/<3?9/@03?9/@@7</?2/A/<5/9/<2707/@9/<@367<55/03?9/@03?9/@@7</?07/@<E/;3<5B;>B:(3?6/A79/<!-"!1 /57/<:3<@/E/<5A30/:/9/<;3<56/;0/A1/6/E/:30760/<E/92/?7>/2/0/57/<:3<@/E/<5A7>7@':369/?3</13>/A?/;0/A1/6/E/272/:/;:3<@/:30769317:2/?7>/2/27B2/?/03?9/@03?9/@@7</?07/@/9/<;3<5B;>B:!AB:/6@30/0<E/:3<@/13;0B<5[email protected]/A9=<C3?53< ).!12).!1)23)-%5!0!$!,%.2!#%-"4.'/E/<5/<03<2/=:36:3<@/13;0B<52/>/A2703<AB923<5/<1/?/;3<55/;0/?9/<@7</?@7</?[email protected];3D/<E/*7</?@7</?[email protected];3D/>/2/:3<@/13;0B<5/2/A75/0B/6E/7AB@30/5/703?79BA/ *7</?E/<52/A/<5@38/8/?@B;0BBA/;/2707/@9/<;3:/:B7A7A794=9B@/9A74:3<@/0 *7</?E/<52/A/<5E/<5;3:/:B7A7A794=9B@>/@742707/@9/<@38/8/?@B;0BBA/;/1 *7</?E/<52/A/<5;3:/:B7>B@/A=>A79A72/9;3<5/:/;7>3;07/@/<Gambar 6.30Lensa cembung bersifat konvergen(mengumpulkan cahaya)Gambar 6.31Lensa cekung bersifat divergen(menyebarkan cahaya)Gambar 6.32Bagian-bagian lensa cembung danlensa cekung(3<3<AB/<@B2BA23C7/@7;7<7;B;;3<55B</9/<>3?@/;//<= K K I= K IIKeterangan:O= pusat optikOF1= jarak fokus dari pusat optikOP1= jari-jari kelengkungan lensaF1 dan F2= titik fokusP1 dan P2= pusat kelengkungan lensaGambar 6.33Sinar-sinar istimewa pada lensacembungF1F1F1F2F2F2(a)(b)(c)F2F1P2POF2F1PP1O

127Cahaya dan OptikaF2F1ABOruangbendaI I IruangbendaI IruangbendaIruangbendaIVruangbayangan(IV )ruangbayangan(I)ruangbayangan(III)ruangbayangan(II)Gambar 6.34Penamaan ruang pada lensacembung !.'+!(0%-"%.34+!."!6!.'!.0!$!,%.2!#%-"4.',<AB9;3;>3?;B2/6>3;03<AB9/<0/E/<5/<?B/<52723>/<2/<2703:/9/<5:3<@/270/57;3<8/270303?/>/?B/<5/<@3>3?A7>/2/!-"!1 03?79BA#3A3?/<5/<!!!!!!2/<!-/2/:/6<=;=??B/<503<2/!!!!!!2/<!-/2/:/6<=;=??B/<50/E/<5/<*3A7/>:3<@/;3;7:7972B/0B/6A7A794=9B@27@303:/697?72/<9/</<<E/"/?/9932B/4=9B@[email protected]@/;/(3?6/A79/<!-"!1 B<AB9;3<55/;0/?9/<0/E/<5/<03<2/E/<5276/@7:9/<=:36:3<@/13;0B<527:/9B9/<1/?/@30/5/703?79BA/ 7:B97@2B/0B/6@7</?[email protected];3D/>/2/:3<@/13;0B<50 *7</?@3:/:B2/A/<52/?7>3?;B9//<:3<@/2/<2707/@9/<9303:/9/<5:3<@/1 (3?>=A=<5/</<A/?/2B/@7</?07/@;3?B>/9/<:3A/90/E/<5/<"79/>3?>=A=<5/<272/>/A2/?7>3?>/<8/<5/<@7</?07/@0/E/<5/<[email protected]/A;/E/2/<27:[email protected]/<23<5/<5/?7@>BAB@>BAB@b.Pembiasan Cahaya pada Lensa Cekung3?032/23<5/<:3<@/13;0B<5:3<@/139B<5[email protected]/A;3<E30/?9/<03?9/@@7</?3?9/@@7</?E/<58/AB6>/2/>3?;B9//<:3<@/139B<5/9/<2707/@9/<@31/?/;3<E30/?).!12).!1)23)-%5!0!$!,%.2!#%+4.'(/2/:3<@/139B<58B5/A3?2/>/A@7</?@7</?[email protected];3D/E/<503?5B</0/57>3;03<AB9/<0/E/<5/<*7</?@7</?[email protected];3D/>/2/:3<@/139B<5/2/:/6@30/5/703?79BA!-"!1 / *7</?E/<52/A/<5@38/8/?@B;0BBA/;/2707/@9/<@3/9/</9/<03?/@/:2/?7A7A794=9B@0 *7</?E/<52/A/<5;3<B8BA7A794=9B@2707/@9/<@38/8/?@B;0BBA/;/1 *7</?E/<52/A/<5;3:/:B7>B@/A=>A79[email protected]/<A72/9;3<5/:/;7>3;07/@/<!.'+!(0%-"%.34+!."!6!.'!.0!$!,%.2!#%+4.'(3?6/A79/<!-"!1 ,<AB9;3<55/;0/?9/<0/E/<5/<03<2/E/<5276/@7:9/<=:36:3<@/139B<527:/9B9/<1/?/@30/5/703?79BA/ 7:B97@2B/0B/6@7</?[email protected];3D/:3<@/139B<50 *7</?@3:/:B2/A/<52/?7>3?;B9//<:3<@/2/<2707/@9/<9303:/9/<5:3<@/1 3<2/E/<527:3A/99/<2723>/<:3<@/139B<5@3:/:B;3<56/@7:/<0/E/<5/<E/<5;3;7:797@74/A;/E/A35/927>3?9317:2/<A3?:3A/92723>/<:3<@/139B<5Gambar 6.36Sinar-sinar istimewa pada lensacekungF1F2F1F2F1F2000Gambar 6.35Pembentukan bayangan oleh lensacembungGambar 6.37Pembentukan bayangan oleh lensacekung(a)(b)(c)F2F1AOBA’B’s’fshh’

128Mudah dan Aktif Belajar Fisika untuk Kelas XK *30B/6:3<@/A7>7@;3;7:7977<239@07/@270/A/@7=:36 >3?;B9//<13;0B<52/<139B<5A7>3/27:3A/99/<27B2/?/"/?78/?7:3<59B<5932B/>3?;B9//<03?AB?BAAB?BA 1;2/< 1; 7AB<58/?/94=9B@:3<@/A7>7@[email protected]!5!"793A/6B7 >3?;B9//<13;0B<5K >3?;B9//<139B<5,<AB9;3<567AB<58/?/94=9B@:3<@/A7>7@2/>/A275B</9/<>3?@/;//<03?79BAK K K 1;"/278/?/94=9B@:3<@/ 1;Contoh 6.12 Gambar 6.38Lensa tipis(a) bikonveks, R1 > 0 ; R2 < 0(b) konvek konkaf, R1 > 0 ; R2 > 0(c) plan konveks, R1 = ; R2 < 0(d) bikonkaf, R1 < 0 ; R2 > 0(e) konkaf konveks, R1 < 0 ; R2 < 0(f ) plan konkaf, R1 = ; R2 > 0 %.2!3)0)2$3<@/A7>7@/2/:/6:3<@/E/<5;3;7:79793A30/:/<8/B6:30769317:270/<27<59/<23<5/<27/;3A3?93:3<59B<5/<<E/$3<@/A7>7@2/>/A27:/;0/<59/<23<5/<@30B/65/?7@(/2/!-"!1 27AB<8B99/<0303?/>/83<7@:3<@/A7>7@/:/;:3<@/A7>7@03?:/9B>3?@/;//<03?79BAK (b)(a)(c)R1R1R2R2(e)(d)(f )R1R2R1R2R1R2R1R2c.Perbesaran Bayangan Lensa(3<53?A7/<>3?03@/?/<0/E/<5/<>/2/:3<@/@/;/23<5/<>3<53?A7/<>3?03@/?/<0/E/<5/<>/2/13?;7<:3<59B<5(3?03@/?/<0/E/<5/<272347<[email protected]/<@30/5/7>3?0/<27<5/</<A/?/A7<5570/E/<5/<2/<A7<55703<2//A/B8/?/90/E/<5/<A3?6/2/>:3<@/2/<8/?/903<2/93:3<@/*31/?/;/A3;/A7@2/>/A27AB:7@/A/B' K #3A3?/<5/<>3?03@/?/<0/E/<5/< 8/?/90/E/<5/<93:3<@/A7<5570/E/<5/<8/?/903<2/93:3<@/A7<55703<2/"79/>[email protected]03?/?A70/E/<5/<[email protected]/A;/E/2/<A35/9"79/K<35/A7403?/?A70/E/<5/<[email protected]/A<E/A/2/<A3?0/:79*30B/603<2/03?27?7A35/9 1;2723>/<:3<@/A7>7@9=<C3?53<E/<58/?/94=9B@<E/1;+3<AB9/</ :3A/90/E/<5/<0 >3?03@/?/<0/E/<5/<1 @74/A0/E/<5/<Contoh 6.13Tugas Anda 6.1Perhatikan kembali gambarpembentukan pada lensacembung dan lensa cekung.Temukan oleh Anda sehinggadiperoleh Persamaan (6–24).Konvensi tanda untuk pembentukanbayangan oleh lensa:Js bernilai + (Objek nyata) untukbenda-benda di depan permukaan(sisi datang);bernilai – (Objek maya)untukbenda-benda di belakangpermukaan (sisi transmisi);Js’ bernilai + (Bayangan nyata)untuk bayangan-bayangan didepan permukaan (sisi transmisi);bernilai – (Bayangan maya) untukbayangan-bayangan di depanpermukaan (sisi datang);Jr, f bernilai + jika pusatkelengkungan berada pada sisitransmisi;bernilai – jika pusat kelengkunganberada pada sisi datang.Ingatlah

129Cahaya dan Optika!5!"793A/6B7 1;2723>/<:3<@/1;:3<@/9=<C3?53</A/B13;0B<5/ $3A/90/E/<5/< K K "/270/E/<5/<03<2/03?/2/ 1;2703:/9/<5:3<@/0 (3?03@/?/<KK 1;% 1; KA/<2/<35/A74;3<B<8B99/<0/E/<5/<<E/A/2/<A3?0/:79"/27>3?03@/?/<0/E/<5/<<E/1 *74/A0/E/<5/<J <E/A/2/<A3?0/:7903?2/@/?9/<<7:/7K<35/A74J @/;/03@/?23<5/<03<2/<E/03?2/@/?9/<<7:/7InformasiSebuah lensa Fresnel adalah lensaplan-konveks yang tebal dibentukberlipat-lipat agar diperoleh lensadatar yang memiliki sifat optiknya,namun lebih tipis sehingga memilikikehilangan penyerapan yang lebihsedikit. Lensa Fresnel biasanya tipisdan lentur, ukurannya sekitar 0,015inch (0,38 mm) dengan alur lekukanpada satu permukaan.Salah satu penerapan lensaFresnel adalah untuk alatpemfokusan sensor inframerah.Lensa Fresnel dapatmemperpanjang rentangpendeteksian mencapai 100 kaki.A Fresnel lens is a plano convex lensthat has been collapsed on it self toform a flat lens that retains its opticalcharacteristics but is much thinnerand therefore has less absorption loss.A Fresnel lens is ussually thin andflexible and is about 0,015 inch (0,38mm) thick with grooves molded onone surface.One of an application of Fresnellens is to focusing devices forinfrared sensors. A Fresnel lens canextend detection range to about100 feet.Sumber: www.glolab.comlensa Fresnelinframerahuntuk AndaInformation for Youd.Kekuatan Lensa"/?/94=9B@@30B/6:3<@/@/<5/A>3<A7<5/?A7<E/9/?3</2/>/A;3<E/A/9/<B9B?/<939B/A/<:3<@/#39B/A/<@30B/6:3<@/@/<5/A03?5/<AB<5>/2/<7:/78/?/94=9B@:3<@/[email protected]#39B/A/<:3<@/@7;0=:272347<[email protected]/<@30/5/793;/;>B/<;3<5B;>B:9/</A/B;3;/<1/?9/<03?9/@1/6/E/3@/?<E/939B/A/<:3<@/03?0/<27<5A3?0/:7923<5/<8/?/94=9B@<E/"79/8/?/94=9B@<E/03@/?939B/A/<:3<@/9317:*30/:79<E/879/8/?/94=9B@:3<@/9317:939B/A/<:3<@/03@/?*31/?/;/A3;/A7@>3?<E/A//<[email protected]27AB:7@K #3A3?/<5/<939B/A/<:3<@/27=>A?78/?/94=9B@;3A3?*/AB/<2/:/;27=>A?7879/8/?/94=9B@:3<@/27<E/A/9/<2/:/;;3A3?,<AB9:3<@/13;0B<5<7:/7(@3:/:B03?<7:/7>[email protected]9/?3</<7:/7>=@7A74*30/:79<E/B<AB9:3<@/139B<5<7:/7 <35/A74K9/?3</<7:/78/?/94=9B@:3<@/139B<5<35/A74K*30B/6:3<@/9=<C3?53<;3;7:7978/?/94=9B@1;3?/>/9/6939B/A/<:3<@/[email protected]!5!"793A/6B71;:3<@/9=<C3?53</A/B13;0B<53?2/@/?9/<>3?@/;//< ;3A3?27=>A?7"/27939B/A/<:3<@/27=>A?7Contoh 6.14

130Mudah dan Aktif Belajar Fisika untuk Kelas Xe.Susunan Dua Lensa:/A/:/A=>A79@3>3?A7;[email protected]=>2/<A3?=>=<5;3<55B</9/<2B/0B/6:3<@//A/B:3076/E/<5/</967?E/<5A3?03<AB9;3?B>/9/<6/@7:2/?7>[email protected]@>3;07/@/<=:36932B/:3<@/[email protected]%B:/;B:/1/6/E/2/?703<2/1/6/E/>/<AB:/<2707/@9/<=:36:3<@/>3?A/;/@367<55/A3?03<AB90/E/<5/<!/E/<5/<!7<793;B27/<@3=:/6=:/6;3?B>/9/<03<2/0/57:3<@/932B//E/<5/<!!/A/B0/E/<5/<A3?/967?A3?03<AB9=:36:3<@/932B//?/;3<3<AB9/<0/E/<5/<0/7923<5/<1/?/5/;0/?;/B>B<1/?/>3?67AB<5/<A3A/>;3<579BA793A3<AB/<E/<5A3:/6270/6/@@303:B;<E/3?2/@/?9/<!-"!1 [email protected]2/<9/?3<//<A/?932B/:3<@/;3;7:7978/?/9A3?A3<AB@7;0=:;/9/A3?2/>/A6B0B<5/<@30/5/703?79BAGambar 6.39Pembentukan bayangan oleh duabuah lensa cembungTes Kompetensi Subbab C%1*!+!.,!($!,!-"4+4,!3)(!. +=5/?@32/<5;3:/9B9/<39@>3?7;3<B<AB9;3<3<AB9/<9313>/A/<1/6/E/272/:/;0/6/<9/1/A30/:!/;3:3>/@9/<@303?9/@1/6/E/>/2/>3?;B9//<9/1/A30/:23<5/<@B2BA I+3?<E/A/03?03:=9272/:/;9/1/23<5/<03@/?>3;03:=9/<A3?6/2/>5/?7@<=?;/: I"79/9313>/A/<1/6/E/27B2/?/ ; @03?/>/9/613>/A?/;0/A1/6/E/272/:/;9/1/A30/:[email protected] "79/7<239@07/@;BA:/9/7?2/<7<239@07/@;BA:/9/:9=6=: A3<AB9/</ 7<239@07/@/7??3:/A74A3?6/2/>/:9=6=:0 7<239@07/@/:9=6=:?3:/A74A3?6/2/>/7? 2/9/66B0B<5/</<A/?/<7:/77<239@07/@2/<93?/>/A/<;/@@/@B/AB03<2/ *30B/603<2/03?27?7A35/92723>/<:3<@/139B<5E/<5;3;7:7978/?/94=9B@ 1;$B97@:/60/E/<5/<03<2/E/<52703<AB9=:3613?;7<139B<5[email protected]879// 03<2/A3?:3A/91;2723>/<:3<@/139B<50 03<2/A3?:3A/9 1;2723>/<:3<@/139B<51 03<2/A3?:3A/9 1;2723>/<:3<@/139B<5 B/0B/6:3<@/13;0B<5[email protected]@B<@323;797/<?B>/@367<55/@B;0BBA/;/03?7;>7A$3<@/>3?A/;/;3;7:7978/?/94=9B@ 1;2/<8/?/94=9B@:3<@/932B/ 1;*30B/603<2/E/<5A7<557<E/1;03?27?7A35/92723>/<:3<@/>3?A/;/>/2/8/?/9 1;+3<AB9/</ 5/;0/?>3;03<AB9/<0/E/<5/</967?0 :3A/90/E/<5/</967?1 A7<5570/E/<5/</967?2/<@74/A0/E/<5/</967?2 >3?03@/?/<A=A/:Kata Kunci•pembiasan (refraksi)•indeks bias•sudut datang•sudut bias•sudut kritis•kaca plan paralel•prisma•deviasi minimum•lensa sferis!!! #3A3?/<5/<8/?/9/<A/?:3<@/ !8/?/90/E/<5/<:3<@/!!!8/?/903<2/:3<@/!!K D. Alat-Alat Optik(3<53A/6B/<;/<[email protected]/;3<53</7=>A79A3:/6;3:/67?9/<723723270B/A<E//:/A/:/A=>A79:/A/:/A=>A79[email protected]8B5/@30/5/7>3?/:/A/<E/<5;3;/<4//A9/<@74/A@74/A0/6/<93A79/2793</71/6/E//6/<0/6/<7<7;3<8/27[email protected];3D/9/?3</03<AB9<E/F2F1F1F2bayanganpertama (I)bayanganakhir (II)lensa II(+)lensa I(+)bendasIs'Is'iIIs'IIL

131Cahaya dan OptikaGambar 6.40Bagian-bagian matafoveapangkalsaraf optikretinasklerairiskorneapupilcairandi sekitar mataotot siliarlensa1.Mata(3?</69/<<2/;3;0/E/<59/<0/5/7;/</879/;/<[email protected]/A72/927:3<59/>723<5/<;/A/>/E/<5<2/?/@/9/<93A79/<2/;3;38/;9/<;/A/B<AB90303?/>/@//A#37<2/6/<2/<67?B9>79B993672B>/<?/@/<E/A72/90357AB03?/?A7/<2/79/A/+B6/<./<5%/6/9B/@/A72/9;3<5/?B<7/9/<;/A/93>/2/<2//5/7;/</>?7<@7>93?8/;/A/93A79/;3:76/A@30B/6=0839(3?6/A79/<:/60/5/<;/A/>/2/!-"!1 (/2/D/9AB;/A/;3:76/A=0839:3<@/;/A//A/B:3<@/[email protected]/:7<;3;03<AB90/E/<5/<03<2/>/2/?3A7</E/<503?/2/270/57/<03:/9/<5;/A/)3A7</7<7276B0B<59/<=:36@/?/4@/?/4>3<5:76/A/<93=A/9@367<55/A7;0B:93@/<;3:76/A03<2//A/B=0839$3<@/;/A/;3?B>/9/<:3<@/E/<5A30/:A7>7@<E/2/>/A03?B0/6@[email protected]/723<5/<:3A/903<2/E/<5@32/<5;3<8/27=0839>3<5:76/A/<(3?B0/6/<A30/:A7>7@<E/:3<@/;/A/7<7;3<5B0/68/?/94=9B@:3<@/;/A/3<5/<1/?/7<7:3A/90/E/<5/<03<2/E/<5@32/<5;3<8/27>3?6/A7/</9/<@3:/:B8/AB6A3>/A27?3A7</@367<55/0/E/<5/<<E/A/2/?703<2/2/>/A27A3?7;/23<5/<83:/@879/0/E/<5/<[email protected]A3>/A8/AB627?3A7</"/?/9?3A7</23<5/<:3<@//2/:/6A3A/>*3;3<A/?/7AB@3A7/>03<2/E/<5;3<8/27>3?6/A7/<;3;7:7978/?/9E/<5A72/9@/;/A3?6/2/>:3<@/;/A/2/03<2/E/<5239/A@32/<52/<8/B60/69/<8/B6@39/:73<2/03<2/[email protected]2/>/AA3?:76/A879/0/E/<5/<03<2/<E/A3>/A8/AB627?3A7</':369/?3</7AB@/AB@/AB<E/1/?/E/<5;B<597</2/:/623<5/<>3?B0/6/<8/?/94=9B@:3<@/;/A/"/27>3?B0/6/<:3<@/;/A/@[email protected]<55B6<E/B<AB9;3<2/>/A9/<0/E/<5/<<E/A/27?3A7</a.Daya Akomodasi#3;/;>B/<:3<@/;/A/B<AB9;3<5B0/68/?/94=9B@<E/[email protected]& (/2/@//A;/A/;3:76/A03<2/E/<5239/A=A=A=A=A@7:7/?;3<35/<5@367<55/:3<@/;/A/:307613;0B<5*30/:79<E/>/2/@//A;3:76/A03<2/E/<58/B6=A=A=A=A@7:7/?;3<53<2B??7:39@@367<55/:3<@/;/A/:3076>7>76(/2/93/2//<<=?;/:=A=A=A=A@7:7/?03?/2/2/:/;93/2//<?7:39@</;B<@3<27>3<579/A2/:/;93/2//<A35/<5(/2/93/2//<7<703<AB9:3<@/;/A//5/92/A/?(/2/93/2//<7<7;/A/2/:/;93/2//<A72/903?/9=;=2/@7"79/03<2/E/<58/B6A/967<55/27239/A9/<=A=A=A=A@7:7/?/9/<;3<8/27A35/<5'A=A@7:7/?/9/<03?A/;0/6A35/<5879/03<2/@3;/97<239/A(/2/93/2//<7<7;/A/2/:/;93/2//<@32/<503?/9=;=2/@7"79/;/A/A3?B@03?/9=;=2/@7;/A/A3?/@/:3:/69/?3</=A=A@7:7/?A3?B@;3<35/<5b.Titik Dekat dan Titik Jauh3<2/6/<E/2/>/AA3?:76/A23<5/<83:/@879/A3?:3A/9272/3?/6>3<5:76/A/<;/A//3?/6>3<5:76/A/<;/A/7<703?/2/27/<A/?/A7A79239/A;/A//A/B"!" %"2/<A7A798/B6/A/B"!"!" "79/03<2/03?/2/27:B/?2/3?/6>3<5:76/A/<[email protected];/A/A72/9/9/<;3:76/A03<2/[email protected]23<5/<83:/@+7A79239/A/2/:/6A7A79A3?239/AE/<52/>/A27:76/A;/A/@31/?/83:/@23<5/<;/A/03?/9=;=2/@7;/[email protected];B;@32/<59/<A7A798/B6/2/:/6A7A79A3?8/B6E/<52/>/A27:76/A;/A/@31/?/83:/@23<5/<;/A/A72/903?/9=;=2/@7(/2/;/A/<=?;/:A7A79A3?8/B6/2/:/627A7A79A/967<55/(3?6/A79/<!-"!1 03?79BAGambar 6.42Daerah penglihatanGambar 6.41Gambaran daya akomodasi matalensa lebih cembungbayangandifokuskan padaretinalensa lebih pipihbenda dekatbenda jauh(a)(b)PP = 25 cmPR = ~jangkauan penglihatan

132Mudah dan Aktif Belajar Fisika untuk Kelas Xc.Cacat Mata dan Penanggulangannya(/2/93<E/A//<<E/;/A/;/<[email protected]/A72/9@3;B/<E/<=?;/:#3A72/9<=?;/:/<;/A/;/<[email protected]/@3?7<5[email protected]1/1/A;/A//A/B/03?/@7(/2/B;B;<E/;/@/:/61/1/A;/A/A3?8/279/?3</0/E/<5/<03<2/A72/9A3>/A8/AB627?3A7</2/E/<5;3<5/:/;71/1/A;/A/9/?3</0/E/<5/<03<2/8/AB62723>/<?3A7</2/</2/>B:/E/<58/AB62703:/9/<5?3A7<//1/A;/A/2/>/A27A/<55B:/<5723<5/<;3<55B</9/<9/1/;/A/:3<@/9=<A/9/A/B=>3?/@7;/A/%/A/<=?;/:/A/B3;3A?=>7/2/:/6;/A/E/<5;3;7:79793;/;>B/<;3:76/A03<2/>/2/2/3?/6>3<5:76/A/<<=?;/:E/7AB/<A/?/A7A79239/A 1;2/<A7A798/B6A/967<55/3?79BA7<70303?/>/83<7@1/1/A;/A/E/<5@3?7<527/:/;7=:36;/<[email protected]/ )/0)!"4.!4(%/A/E/<5;3<5/:/;71/1/A;7=>7E/7AB;/A/E/<5;3;7:797A7A79239/A@/;/23<5/< 1; 1;2/<;3;7:797A7A798/B6A3?A3<AB (3<23?7A/1/1/A;/A/7<7A72/92/>/A;3:76/A03<2/E/<58/B6@30/0:3<@/;/A/;7=>7;3<13;0B<52/<A72/92/>/A;3<8/27>7>76@30/5/7;/</;/A/<=?;/:970/A<E/0/E/<5/<03<2/8/B6@3:/:B8/AB62723>/<?3A7</,<AB9;3</<55B:/<571/1/A;/A/;7=>76/?B@27B>/E/9/</5/?0/E/<5/<A3>/A8/AB627?3A7</3?/?A7@303:B;@7</?2/A/<58/AB6>/2/:3<@/;/A/A3?:30762/6B:B@7</?2/A/<57<76/?B@[email protected]/?9/<':369/?3</7AB6/?B@270/<AB=:36:3<@/139B<5:3<@/27C3?53<E/<5939B/A/<:3<@/<E/@323;797/<?B>/@367<55/;/;>B;3;03<AB90/E/<5/<03<2/A3>/A8/AB6"79/:3<@/;/A/27/<55/>@43?7@0=:/23<5/<8/?/9>3?;B9//<23>/<:3<@/23<5/<?3A7</ 1;67AB<5:/6/ 9B/A:3<@/;/A/<=?;/:93A79/;/A/;3:76/A03<2/E/<58/B6@39/:7;/A/A72/903?/9=;=2/@72/<93A79/;3:76/A03<2/>/2/8/?/9 1;;/A/03?/9=;=2/@7;/[email protected];B;0 >3?B0/6/<939B/A/<:3<@/;/A/2/?7A72/903?/9=;=2/@7@/;>/703?/9=;=2/@7;/[email protected];B;!5!"793A/6B7 1;/ (/2/@//A;/A/A72/903?/9=;=2/@7 1; ; 27=>A?7(/2/@//A;/A/03?/9=;=2/@7 1; 1; ; 27=>A?7"/279B/A;/A/<=?;/:>/2/@//AA72/903?/9=;=2/@7/2/:/6 27=>A?72/<>/2/@//A;/A/03?/9=;=2/@7/2/:/6 27=>A?70 (3?B0/6/<939B/A/<:3<@/ K K27=>A?7"/27>3?B0/6/<939B/A/<:3<@/K 27=>A?7Contoh 6.15Gambar 6.43(a) Pada cacat mata miopi, bayanganbenda selalu jatuh di depanretina.(b) Cacat mata miopi diatasi denganmenggunakan lensa cekung.sinar-sinarsejajar daribenda jauhlensa cekung(a)(b)

133Cahaya dan Optika2/<K K 27?3A7</5/?2/>/A;3:76/A03<2/03<2/8/B6>3<23?7A/?/0B<8/B66/?B@;3<55B</9/<:3<@/9/1/;/A/E/<5;3<56/@7:9/<0/E/<5/<;/E/2723>/<:3<@/>/2/8/?/9E/<5@/;/23<5/<A7A798/B6<E/ "/27B<AB9>3<23?7A/?/0B<8/B6/A/B;7=>703?:/9BContoh 6.16 )0%1-%31/0)!"4.%+!3%/A/E/<5;3<5/:/;71/1/A67>3?;3A?=>7E/7AB;/A/E/<5;3;7:797A7A79239/A:307603@/?2/?7>/2/ 1;2/<;3;7:797A7A798/B6A/967<55/(3<23?7A/1/1/A;/A/7<7A72/92/>/A;3:76/A03<2/E/<5239/AA3A/>72/>/A;3:76/A83:/@03<2/03<2/8/B6A/<>/03?/9=;=2/@7/1/A7<7A3?8/279/?3<//2/:/6;/A/A72/92/>/A;3<8/2713;0B<5@30/5/7;/</;/A/<=?;/:970/A<E/0/E/<5/<03<2/239/A@3:/:B8/AB62703:/9/<5?3A7</,<AB9;3</<55B:/<571/1/A;/A/67>3?;3A?=>76/?B@27B>/E/9/</5/?0/E/<5/<A3>/A8/AB627?3A7</3?/?A7@303:B;@7</?2/A/<58/AB6>/2/:3<@/;/A/A3?:30762/6B:B@7</?2/A/<57<76/?B@;3<5B;>B:':369/?3</7AB>3<23?7A/6/?B@270/<AB23<5/<:3<@/13;0B<5:3<@/9=<C3?53<E/<5939B/A/<:3<@/<E/;/;>B;3;03<AB90/E/<5/<03<2/@367<55/A3>/A8/AB627?3A7</(3?6/A79/<!-"!1 5/?>3<23?7A/2/>/A;3:76/A03<2/03<2/239/A>/2/8/?/9A3?A3<AB>3<23?7A/?/0B<239/A6/?B@;3<55B</9/<:3<@/9/1/;/A/E/<5;3<56/@7:9/<0/E/<5/<;/E/2723>/<:3<@/>/2/8/?/9E/<5@/;/23<5/<A7A79239/A<E/K"/27B<AB9>3<23?7A/67>3?;3A?=>703?:/9BKK Gambar 6.44(a) Pada cacat mata hipermetropi,bayangan benda selalu jatuh dibelakang retina.(b) Cacat mata hipermetropi diatasidengan menggunakan lensacembung.benda dekatlensa cembungretina(a)(b)*[email protected]=?/<5E/<5;3<23?7A/67>3?;3A?=>7;3;7:797A7A79239/A 1;5/?2/>/A;3:76/A03<2/03<2/E/<5239/A@3>3?A7;/A/<=?;/:03?/>/9/68/?/94=9B@2/<9B/A:3<@/E/<56/?B@7/5B</9/<!5!"793A/6B7 K 1;A7A79239/A>3<23?7A/67>3?;3A?=>7 K 1; ;Contoh 6.17Tanda negatif menunjukkan bahwapenderita miopi harus dibantudengan lensa negatif atau lensacekung (lensa divergen).Ingatlah*[email protected]=?/<5E/<5;3<23?7A/;7=>7;3;7:797A7A798/B6 1;5/?7/2/>/A;3:76/A03<2/03<2/E/<58/B603?/>/9/68/?/94=9B@2/<9B/A:3<@/E/<56/?B@275B</9/<>3<23?7A/;7=>7[email protected]!5!"793A/6B7 K 1;A7A798/B6>3<23?7A/;7=>7 K 1;K 1;K; K /A/B K 27=>A?7K 1;"/278/?/94=9B@:3<@/K;2/<939B/A/<<E//2/:/61427=>A?7

134Mudah dan Aktif Belajar Fisika untuk Kelas X 1%2")/0)!3! 4!%/A/AB/;3;7:797=A=A@7:7/?E/<5A72/9:/570/79@3>3?A7>/2/;/A/<=?;/:970/A<E/93;/;>B/<=A=AB<AB903?/9=;=2/@7/A/B;3<5B0/68/?/94=9B@:3<@/;/A/A72/9@30/79@3>3?A7>/2/;/A/<=?;/:(3<23?7A/1/1/A>[email protected]=>7;3;7:797A7A79239/A:307603@/?2/?7>/2/ 1;2/<A7A798/B6>/2/8/?/9A3?A3<AB@367<55/>3<23?7A/>[email protected]=>7A72/92/>/A;3:76/A/A/B;3;0/1/>/2/8/?/9<=?;/:2/<A72/92/>/A;3:76/A03<2/8/B623<5/<83:/@/1/A;/A/>[email protected]=>72/>/A27A/<55B:/<57;3<55B</9/<:3<@/?/<59/>@3>3?A7>/2/!-"!1 #/1/;/A/7<7A3?27?7/A/@:3<@/13;0B<52/<139B<5,<AB9;3:76/A03<2/8/B6>3<23?7A/>[email protected]=>72/>/A;3<55B</9/<:3<@/139B<52/>B<B<AB9;3:76/A03<2/>/2/8/?/9<=?;/:>3<23?7A/>[email protected]=>72/>/A;3<55B</9/<:3<@/13;0B<5*[email protected]=?/<59/939>3<23?7A/>[email protected]=>7;3;7:797A7A79239/A1;2/<A7A798/B6 1;5/?7/2/>/A;3:76/A03<2/E/<5239/A@3>3?A7;/A/<=?;/:2/<2/>/A;3:76/A03<2/8/B603?/>/9/68/?/94=9B@:3<@/074=9/:2/<9B/A:3<@/9/1/;/A/E/<56/?B@275B</9/<9/939[email protected]!5!"#/1/;/A/074=9/:[email protected]@B</A/@2B/:3<@/0/57/</A/@:3<@/<35/A74139B<5/5/?2/>/A;3:76/A8/B62/<0/57/<0/D/6:3<@/>[email protected]13;0B<5/5/?2/>/A;3;0/1/<=?;/:J ,<AB92/>/A;3:76/A8/B62/<K 1; KK K 1;K ;K K 27=>A?7"/27B<AB92/>/A;3:76/A03<2/8/B6275B</9/<9/1/;/A/23<5/<8/?/94=9B@ ;2/<939B/A/<:3<@/K 27=>A?7J ,<AB92/>/A;3:76/A03<2/239/A 2/<K1; K 1; ; 27=>A?7"/27B<AB92/>/A;3:76/A03<2/239/A275B</9/<9/1/;/A/23<5/<8/?/94=9B@ ;2/<939B/A/<:3<@/ 27=>A?7Contoh 6.18110,5f 27=>A?7"/278/?/94=9B@:3<@//2/:/6 ;2/<939B/A/<03@/?<E//2/:/6 27=>A?7Gambar 6.45Kacamata bifokal. Lensa (–) untukmelihat jauh, lensa (+) untuk melihatdekat. 23)'-!3)2-!@A75;/A7@;/;3?B>/9/<1/1/A;/A/E/<527/970/A9/<03<AB99=?<3/A72/90B<2/?/1/A;/A//@A75;/A7@;/2/>/A27A/<55B:/<5723<5/<:3<@/@7:7<2?7@$3<@/7<72/>/A;3<5B;>B:9/</A/B;3<E30/?9/<@7</?>/2/@/AB/?/6@/8/A/<>/;3;3<5/?B67/?/6:/7<2.Lup (Kaca Pembesar),<AB92/>/A;3:76/A03<2/03<2/9317:/5/?A/;>/9:307603@/?2/?7>/2/B9B?/<@303</?<E/275B</9/<:B>$B>;3?B>/9/<:3<@/13;0B<5Pada Contoh Soal 6.18, tandapositif menunjukkan bahwapenderita hipermetropi harusdibantu dengan lensa positif ataulensa cembung (lensa konvergen).Ingatlah

135Cahaya dan Optika/<5B:3? K "79/;/A/03?/9=;=2/@7>/2/8/?/9%;/E/27>3?=:36>3?@/;//<K % %% %K "79/%12!-!!. 7 [email protected]@[email protected]/<93%12!-!!. 7 /9/<27>3?=:36/<5B:3? % % %%%/<5B:/?%K #3A3?/<5/</<5B:3?>3?03@/?/</<5B:3?A7A79239/A;/A/8/?/94=9B@:B>%8/?/9/<A/?/0/E/<5/< 2/<:B>"K "79/@B2BA2/<@/<5/A9317:A/<2/<A/<;/9/"K ':369/?3</ 2/< ;/9/%12!-!!. 7 ;3<8/27/A/B:3<@/>[email protected]*30/5/7;/</<2/93A/6B7:3<@/13;0B<5;3;7:79793;/;>B/<;3;03<AB90/E/<5/<;/E/E/<527>3?03@/?879/03<2/A3?:3A/927/<A/?/A7A794=9B@2/<:3<@/,<AB9:B>03<2/@3:/:B27:3A/99/<2/:/;?B/<5!@367<55/0/E/<5/</9/<A3?:3A/927?B/<5!-/E/<5/<E/<5A3?:3A/927?B/<5!-[email protected]/A;/E/2/<A35/9@367<55/8/?/90/E/<5/<E/<52703<AB9:B>@3:/:B<35/A7403?A/<2/<35/A74(/2/@//A;3<55B</9/<:B>8/?/903<2/27B0/6B0/6@323;797/<?B>/@367<55/272/>/A9/<0/E/<5/<E/<5>/:7<583:/@0/57;/A/<=?;/:E/7AB>/2/8/?/90/1/E/<507/@/<E/ 1;(3?6/A79/<!-"!1 (3?6/A79/<!-"!1 !2/< "+/<>/:B>03<2/A3?:76/A23<5/<@B2BA@303@/?2/>B<879/;3<55B</9/<:B>03<2/A3?:76/A=:36;/A/23<5/<@B2BA@367<55/>3?03@/?/</<5B:3?<E/@303@/?Gambar 6.46Lup digunakan juga untuk memperjelastulisan yang sangat kecil.PPpGambar 6.47(a)Sudut penglihatan mata (),ketika benda dilihat tidakmenggunakan lup.(b) Sudut penglihatan mata (),ketika benda dilihat denganmenggunakan lup.FFp'(a)(b)sPs' = PP*30B/6:B>;3;7:7978/?/94=9B@ 1; 7AB<5:/6>3?03@/?/<:B>879/;/A/;3:76/A03<2/23<5/<03?/9=;=2/@7>/2/8/?/9 1;Contoh 6.19

136Mudah dan Aktif Belajar Fisika untuk Kelas XmatapengamatbayanganLokulerbendasobs'obsokFokF 'obFobobjektif(a)Lokulerbendasobs'obsokFokF 'obFobobjektif(b)matapengamat=0 =9K #3A3?/<5/<>/<8/<5;[email protected]=>=08/?/90/E/<5/<0/57:3<@/=0839A74=98/?/903<2/0/57:3<@/=9B:3?Gambar 6.49Pembentukan bayangan padamikroskop:a. Untuk mata berakomodasimaksimum;b. Untuk mata tidak berakomodasi.(3?6/A79/<!-"!1 (/<8/<5;[email protected]=>2/>/A271/?723<5/<;3<55B</9/<>3?@/;//<3.Mikroskop%[email protected]=>/2/:/6@30B/6/:/A=>A79E/<5275B</9/<;3:76/A03<2/03<2/@/<5/A9317:1=<A=6<E/C7?B@2/<0/9A3?7%[email protected]=>;3;7:797>3?03@/?/</<5B:3?:307603@/?2/?7>/2/:B>%[email protected]=>A3?27?7/A/@2B/:3<@/13;0B<5$3<@/E/<5239/A23<5/<;/A/[email protected]:3<@/=9B:3?@32/<59/<:3<@/E/<5239/A23<5/<03<2/[email protected]:3<@/=0839A74(3?6/A79/<@93;/@[email protected]</<:3<@/;[email protected]=>>/2/!-"!1 /E/<5/</967?E/<5276/@7:9/<=:362B/:3<@/2/:/;;[email protected]=>[email protected]/A;/E/27>3?03@/?2/<A3?0/:79A3?6/2/>03<2/@3;B:/Gambar 6.48Mikroskoplensaobjektifbendalensaokuler!5!"793A/6B7 1; 1;/ (3?03@/?/</<5B:3?/<5B:3?93A79/;/A/03?/9=;=2/@7>/2/8/?/9 1;,<AB9;3<567AB<5>3?03@/?/<7<7275B</9/<%12!-!!. 7 03?79BA/<5B:3?%&7:/7%27>3?=:3623<5/<>3?@/;//<03?79BA ' ' 1; 1; 1; 1;K 1; 1; 1;/:/;6/:7<7%3<5/<23;797/<>3?03@/?/</<5B:3?/2/:/6/<5B:3?%/<5B:3? %%%0’sf 1; "/27>3?03@/?/<:7<3/?:B>B<AB9;/A/A/903?/9=;=2/@7@303@/?

137Cahaya dan Optika•Apabila jarak bayangan yangdihasilkan lup adalah (s’ = –x),artinya mata berakomodasipada jarak x sehinggaperbesaran sudutnya adalahangulerPPPPM=+fx•Untuk mata berakomodasimaksimum, bayangan yang di-bentuk oleh lup terletak dititik dekat mata (s’ = –PP)s’ = –x = –PPx = PPangulerPPPPM=+fPPPP=+f1•Untuk mata tidakberakomodasi, bayangan yangdibentuk oleh lup terletak dititik jauh mata (s’ = –PR).Untuk mata normal,PR = maka s’ = . Agarjarak s’ = – maka bendaharus diletakkan di titikfokus F.s’ = –x = – x = angulerPPPPM=+fxPP=+f0PP=fIngatlah(3?03@/?/<=:36:3<@/=0839A74/2/:/6=0=0 =0=0 =0 K <=9=9K =0L=9K (3?03@/?/<A=A/:@30B/6;[email protected]=>/2/:/6@30/5/703?79BA<=9=9#3A3?/<5/<=0>3?03@/?/<:3<@/=0839A74=08/?/90/E/<5/<0/57:3<@/=0839A74=08/?/903<2/0/57:3<@/=0839A74=0A7<5570/E/<5/<=0A7<55703<2/':369/?3</:3<@/=9B:3?[email protected]/A@30/5/7:B>;/9/>3?03@/?/<:3<@/=9B:3?;[email protected]=>/2/:/6@30/5/703?79BA,<AB9;/A/03?/9=;=2/@7;/[email protected];B;K #3A3?/<5/<8/?/9A7A79239/A;/A/<=?;/:=98/?/94=9B@=9B:3?,<AB9;/A/A72/903?/9=;=2/@7Tantanganuntuk AndaPelangi adalah hasil peristiwa optikayang melibatkan butiran hujan,cahaya matahari, dan mata.Gambarkan peristiwa optikatersebut sehingga Andamendapatkan sensasi keindahan itu.*30B/6;[email protected]=>;3;7:797:3<@/=0839A7423<5/<8/?/94=9B@ 1;2/<:3<@/=9B:3?23<5/<8/?/94=9B@1;"79/8/?/9/<A/?:3<@/ 1;67AB<5>3?03@/?/<A=A/:;[email protected]=>>/2/@//A/ ;/A/03?/9=;=2/@7;/[email protected];B;0 ;/A/A72/903?/9=;=2/@7!5!"793A/6B7=0 1; 1;=91;/ (3?03@/?/<>/2/@//A;/A/03?/9=;=2/@7;/[email protected];B;;/A/27/<55/><=?;/:=9K 1;=9 =9=9 =9 =9=9 =9 =9=9=9 =9 =9 =9=9=9 =9 =91;K 1; K 1;K 1; K 1; K 1;=91;Contoh 6.213?2/@/?9/<?B;B@ =0 =9 =0=0 K 1;3<5/<;3<55B</9/<?B;B@:3<@/A7>7@27>3?=:36=0 =0=0 =0 =0=0 =0 =0=0=0 =0 =0 =0=0=0 =0

138Mudah dan Aktif Belajar Fisika untuk Kelas X(3?03@/?/<=:36:3<@/=9B:3?=9=9 1; 1;"/27>3?03@/?/<A=A/:;[email protected]=>>/2/@//A;/A/03?/9=;=2/@7;/[email protected];B;/2/:/6=0L=99/:70 ,<AB9;/A/A72/903?/9=;=2/@7=9=91;=0 =9 =01;=0 1;3?2/@/?9/<?B;B@:3<@/A7>7@=0 =0=0 =0 =0=0 =0 =0=0 =0 =0 =0=0=0 =0 1; 1; 1; 1; K 1; 1; 1;(3?03@/?/<=:36:3<@/=0839A74=0=0=0 1; 1; 9/:7(3?03@/?/<=:36:3<@/=9B:3?=9=9 1;1;"/27>3?03@/?/<A=A/:;[email protected]=>>/2/@//A;/A/A72/903?/9=;=2/@7/2/:/6=0L=9 Tugas Anda 6.2Anda mungkin pernah melihathasil suatu pencitraan luar angkasayang diperoleh dari teleskopHubble. Bagaimanakah prinsipFisika yang diterapkan padateleskop luar angkasa tersebut?4.Teropong atau Teleskop+3?=>=<5/A/BA3:[email protected]=>;3?B>/9/</:/A=>A79E/<52/>/A275B</9/<B<AB9;3:76/A03<2/03<2/E/<58/B6@367<55/A/;>/9:3076239/A2/<:307683:/@(/2/ !,),%/;3;0B/A@30B/6A3:[email protected]=>E/<5A3?27?7/A/@2B/:3<@/2/<@30B/6>7>/=?5/</@30/5/7A/0B<5<E/*3A3:/67AB!,),%/8B5/;3;0B/A03?;/1/;;/1/;A3:[email protected]=>2/<;3<3;B9/<0/<E/9>3<3;B/<2/:/;072/<5@A?=<=;7*39/?/<52793</:2B/;/1/;A3:[email protected]=>E/7ABA3:[email protected]=>07/@2/<A3:3@9=>>/<AB: +3:[email protected]=>07/@A3?27?7/A/@0303?/>/:3<@/E/<503?4B<[email protected];3;07/@9/<@7</?2/A/<52/?703<2/+3:[email protected]=>E/<5A3?;/@B99/A35=?7A3:[email protected]=>07/@27/<A/?/<E/A3:[email protected]=>07<A/<5A3:[email protected]=>B;7A3:[email protected]=>>/<55B<52/<A3:[email protected]=>>?7@;/ +3:[email protected]=>>/<AB:A3?27?7/A/@0303?/>/13?;7<@30/5/7>3;/<AB:2/<:3<@/@30/5/7>3;07/@@7</?2/A/<52/?703<2/! %,%2+/0).3!.'+3:[email protected]=>07<A/<5A3?27?7/A/@2B/:3<@/E/7AB:3<@/=0839A742/<:3<@/=9B:3?!-"!1 03?79BA7<7;3<B<8B99/<>[email protected]@>3;03<AB9/<0/E/<5/</967?2/?7@B/ABA3:[email protected]=>07<A/<5=0 1; 1; 1; 1; K 1; 1; 1;(3?03@/?/<=:36:3<@/=0839A74=0=0=0 1; 1;9/:7

139Cahaya dan Optikaobjektif(+)okuler(–)Ls'obsoksob = ~s'ok = – ~matapengamatGambar 6.50Pembentukan bayangan olehteleskop bintang pada mata yangberakomodasi maksimum.=0=9K (/<8/<5A3:[email protected]=>07<A/<5879/;/A/03?/9=;=2/@7/2/:/6K /<>/<8/<5A3:[email protected]=>07<A/<5>/2/@//AA72/903?/9=;=2/@7/2/:/6=0=9#3A3?/<5/<>/<8/<5A3?=>=<5=98/?/903<2/0/57:3<@/=9B:3?=08/?/90/E/<5/<0/57:3<@/=0839A74=08/?/94=9B@:3<@/=0839A74=98/?/94=9B@:3<@/=9B:3?(3?03@/?/</<5B:3?A3:[email protected]=>07<A/<5/2/:/6A/<A/<a/A/B=0/<5B:3?=9#3A3?/<5/</<5B:3?>3?03@/?/</<5B:3?K(/2/@//A53?6/</%/A/6/?7@3=?/<5>3<3:7A753?6/</;3<5/;/A7<E/23<5/<@30B/6A3:[email protected]=>07<A/<5$3<@/=0839A742/<=9B:3?E/<5275B</9/<;3;7:7978/?/94=9B@;/@7<5;/@7<5 1;2/< 1;"79/@B2BA27/;3A3?%/A/6/?727:76/A23<5/<;/A/A3:/<8/<5 I03?/>/23?/8/A@B2BA27/;3A3?%/A/6/?7>/2/@//A27/;/A7;3<55B</9/<A3:[email protected]=>07<A/<5[email protected]!5!"793A/6B7=0 1;=9 1; IJ (/2/:3<@/=0839A74%/A/6/?703?/2/>/2/A7A79E/<58/B6@39/:7@367<55/=0/970/A<E/=0=0 1;J (/2/:3<@/=9B:3?,<AB9;3<5/;/A703<2/:/<57A07/@/<E/;/A/A72/903?/9=;=2/@7/E/<5/<=:36:3<@/=9B:3?6/?B@8/AB627A7A79A/967<55/=9"79/0/E/<5/<A3?:3A/927A/967<55/2/>/A27>/@A79/<03<2/03?/2/274=9B@=9=9 1;Contoh 6.22

140Mudah dan Aktif Belajar Fisika untuk Kelas X# %,%2+/01)2-!+3:[email protected]=>>?7@;/[email protected]8B5/A3:[email protected]=>07<=9B:3?B<[email protected]A3:[email protected]=>7<7@/;/23<5/<A3:[email protected]=>B;7"79/>/2/A3:[email protected]=>B;727:3<59/>723<5/<:3<@/>3;0/:79@32/<59/<A3:[email protected]=>>?7@;/27:3<59/>723<5/<>?7@;/@79B@79BB<[email protected]>?7@;/7<7B<AB9;3;0/:799/<0/E/<5/<(3<55B<//<>?7@;/27;/9@B29/</5/?A3:[email protected]=>7<7A72/9A3?:/:B>/<8/<52/<>?/9A7@B<AB9275B</9/<+3:[email protected]=>>?7@;/27AB<8B99/<>/2/!-"!1 *3A7/>A3:[email protected]=>>?7@;/07/@/<E/27:3<59/>723<5/<7<4=?;/@7<=;=?@3>3?A7L /A/B L <59/>3?A/;/;3<B<8B99/<>3?03@/?/<2/</<59/932B/;3<B<8B99/<27/;3A3?:3<@/=0839A742/:/;;7:7;3A3?$ %,%2+/0!,),%) %,%2+/0!.''4.'+3:[email protected]=>7<7;3?B>/9/<;=27479/@72/?7A3:[email protected]=>B;7(3;0/:79/<0/E/<5/<2/:/;A3:[email protected]=>7<727:/9B9/<23<5/<;3<55B</9/<:3<@/139B<5@30/5/7:3<@/=9B:3?<E/+3:[email protected]=>7<7@3?7<58B5/[email protected]A3:[email protected]=>>/<55B<5/A/BA3:[email protected]=>/:7:37(3?6/A79/<!-"!1 Gambar 6.52Teleskop prismaobjektifokulerokulerGambar 6.51Pembentukan bayangan padateleskop Bumi oleh mata yangberakomodasi maksimum.Pada teropong bintang ....(1) bayangan oleh lensa objektifterletak di titik api II.(2) titik api II lensa objektifdiimpitkan dengan titik api Ilensa okuler(3) bayangan akhir terletak di takterhingga(4) bayangan akhir terbalikUMPTN, 1993Jawaban : DPembahasan SoalJ (3?03@/?/<A3:[email protected]=>=0=9 1; 1; 9/:7"/27@B2BA27/;3A3?;/A/6/?793A79/27/;/A7;3<55B</9/<A3:[email protected]=>/2/:/6 I II" %,%2+/04-)+3:[email protected]=>7<7275B</9/<B<AB92/>/A;3:76/A03<2/03<2/8/B627>3?;B9//<B;7/E/<5/</967?E/<5276/@7:9/<A3<AB6/?B@[email protected]/AA35/92/<27>3?03@/?':369/?3</7ABA3:[email protected]=>B;727:3<59/>723<5/<@30B/6:3<@/E/<503?4B<[email protected]B<AB9;3;0/:799/<0/E/<5/<$3<@/[email protected]27</;/9/<:3<@/>3;0/:79$3<@/7<727:3A/99/<27/<A/?/:3<@/=0839A742/<:3<@/=9B:3?(3?6/A79/<5/;0/?>3;03<AB9/<0/E/<5/</967?=:36@30B/6A3:[email protected]=>B;703?79BA7<7!-"!1 3?2/@/?9/<!-"!1 >/<8/<5A3:[email protected]=>B;7/2/:/6=0=9K #3A3?/<5/<8/?/94=9B@:3<@/>3;0/:79 >/<8/<5A3:[email protected]=>B;7pembentuk(+)okuler(+)objektif(+)fobfobFob4fpfokFpFpFokFokSumber: Jendela Iptek, 1997matapengamat

141Cahaya dan Optikabayangansob = ~okuler(–)objektif(+)s'obsokFokFobFokmatapengamatGambar 6.53Pembentukan bayangan olehteleskop panggung oleh mata yangberakomodasi.*30B/6A3:[email protected]=>/:7:37E/<5;3;7:797>3?03@/?/</<5B:3?9/:72/<;3;7:7978/?/94=9B@=0839A74 1;275B</9/<B<AB9;3<E3:72797@30B/603<2/E/<5A3?:3A/9@/<5/A8/B6 7AB<5>/<8/<5A3:[email protected]=>/:7:377<7!5!"793A/6B7=0 1;/<5B:3?9/:7':369/?3</2/:/;A3:[email protected]=>7<7:3<@/=9B:3?<E/:3<@/139B<503?/?A7=903?<7:/7<35/A74"/278/?/94=9B@:3<@/=9B:3?/2/:/6K 1;@367<55/ =0=9 K 1;"/27>/<8/<5A3:[email protected]=>/:7:37/2/:/6 1;/A/B;3?2/@/?9/<!-"!1 >3?03@/?/</<5B:3?A3:[email protected]=>/:7:37/2/:/6=0/<5B:3?=9K 2/>B<>/<8/<5A3:[email protected]=>/:7:37@303@/? =0=9KContoh 6.23Tugas Anda 6.3Anda mengenal ada dua macamteleskop, yaitu teleskop bias danteleskop pantul. Mengapateleskop pantul yang berukuranbesar lebih mudah dibuatdibandingkan dengan teleskopbias?% %,%2+/0!.34,+3:[email protected]=>7<727:3<59/>723<5/<13?;7<139B<503@/?@30/5/713?;7<=0839A74<E/*3:/7<7AB27:3<59/>7>B:/23<5/<13?;7<2/A/?2/<:3<@/13;0B<5@30/5/7=9B:3?<E/3?;7<2/A/?03?4B<[email protected]B<AB9;3;/<AB:9/<1/6/E/':369/?3</7ABA3:[email protected]=>7<7[email protected]A3:[email protected]=>>/<AB:(3?8/:/</<@7</?E/<5A3?8/27>/2/A3:[email protected]=>>/<AB:27AB<8B99/<=:36!-"!1 sinar sejajar daribintang/bulanyang jauhcermincekunglensa cembung(okuler)FGambar 6.54Teleskop pantul

142Mudah dan Aktif Belajar Fisika untuk Kelas X*30B/69/;3?/;3;7:797A7A79/>7 ;;/D/:<E/275B</9/<B<AB9;3<5/;07:5/;0/?03<2/E/<51B9B>8/B6#3;B27/<9/;3?/275B</9/<B<AB9;3<5/;07:5/;0/?@30B/603<2/E/<58/?/9<E/ ;2/?7:3<@/+3<AB9/<93;/</2/<03?/>/8/B6:3<@/9/;3?/6/?B@[email protected]?!5!"793A/6B7 ;; ;#3/2//<;B:/;B:/G;/9/ ;#3/2//</967?B<AB9 ; K ;3@/?>[email protected]?/<:3<@/9/;3?//2/:/6K K ; ;;':369/?3</;/9/ /?A7<E/:3<@/9/;3?/6/?B@[email protected]?;3<8/B6747:;Gambar 6.56Penjalaran sinar pada kameraContoh 6.24cahayakacaprisma& !-%1!#/;3?//2/:/6/:/AB<AB9;3?39/;5/;0/?2/?7@B/AB=083903?B>/A3;>/A/A/B>3[email protected]/(?7<@7>93?8/9/;3?/;7?7>23<5/<;/A/$3<@/9/;3?/;3?B>/9/<0/57/<2/?79/;3?/E/<503?4B<[email protected]B<AB9;3;03<AB90/E/<5/<;7?7>:3<@/;/A/>/2/;/A/#/;3?/27:3<59/>723<5/<47:;E/<503?4B<[email protected]@30/5/7A3;>/A0/E/<5/<;7?7>23<5/<?3A7</>/2/;/A/"79/;/A/;3;7:79793;/;>B/<B<AB903?/9=;=2/@7>/2/9/;3?/>3<5/AB?/<0/E/<5/</5/?8/AB6A3>/A>/2/47:;27:/9B9/<23<5/<1/?/;3<553?/99/<:3<@/!-"!1 ;3<B<8B99/<@30B/69/;3?/:3<59/>23<5/<0/57/<0/57/<<E/([email protected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ambar 6.55Kamera dan bagian-bagiannyakacalensacahayaprismafilmlensaprismamatakacacahayaKata Kunci•daya akomodasi•punctum proximum•punctum remotum•emetropi•miopi•hipermetropi•presbiopi•astigmatisma•lup•mikroskop•teropong/teleskop•teleskop bintang•teleskop bumi•teleskop Galilei•kamera

143Cahaya dan Optika<2/07@/;3;>3?=:36B?/7/<;/A3?7;3<53</70/07<723<5/< 27$$$/A/B23<5/<;3<5B<8B<57@7AB@7<A3?<3A;3<53</71/6/E/2/<=>A79/@27/<A/?/<E//2/:/627! "" !!!!! !Mari Mencari Tahu23<5/<@E/?/A932B/;327B;[email protected];3;7:7977<239@07/@E/<503?032/ (3;07/@/<A3?8/278B5/>/2/:3<@/13;0B<52/<:3<@/139B<5 /1/A ;/A/ A3?8/27 07/@/<E/ 9/?3</0/E/<5/<03<2/A72/9A3>/A8/AB627?3A7</ %/A/:B>;[email protected]=>A3?=>=<52/<9/;3?/;3?B>/9/<1=<A=6/:/A/:/A=>A79Rangkuman 2/2B/A3=?7A3<A/<51/6/E/E/7ABA3=?7>/?A793:2/<A3=?753:=;0/<5+3=?7>/?A793::/67?2/?70B/6>797?/<2!!#%53/.E/<503?>3<2/>/A 0/6D/ 1/6/E/ ;3?B>/9/<>/?A793:2/>B<A3=?753:=;0/<5:/67?2/?70B/6>797?/<46'%.2E/<503?>3<2/>/A0/6D/1/6/E/;3?B>/9/<53:=;0/<5 /6/E/2/>/A27>/<AB:9/<2/<2707/@9/< (3;07/@/<1/6/E/6/<E/A3?8/27879/1/6/E/2/A/<52/?7@B/AB;327B;93;327B;:/7<Tes Kompetensi Subbab D *3=?/<5A3;/<<2/;3<55B</9/<:3<@/139B<5K27=>A?73?/>/9/68/?/94=9B@:3<@/2/<A7A798/B6E/<5;/@762/>/A27:76/A=:36A3;/<<2/[email protected]93A79/7/A72/903?9/1/;/A/*30B/69/1/>3;03@/?;3;7:797939B/A/<:3<@/ 27=>A?7+3<AB9/<>3?03@/?/<:B>B<AB9;/A/03?/9=;=2/@7;/[email protected];B;2/<A72/903?/9=;=2/@7 *30B/6;[email protected]=>;3;7:7978/?/94=9B@:3<@/=0839A742/<:3<@/=9B:3?03?AB?BAAB?BA ;;2/<1;"79/@30B/603<2/27:3A/99/<;;2723>/<:3<@/=0839A74@32/<59/<8/?/9/<A/?:3<@//2/:/61; 7AB<5>3?03@/?/<E/<5276/@7:9/<B<AB9;/A/<=?;/:A72/903?9/1/;/A/ *30B/6A3:[email protected]=>07<A/<5;3;7:797:3<@/=0839A7423<5/<8/?/94=9B@<E/ 1;2/<:3<@/=9B:3?E/<58/?/94=9B@<E/1; 7AB<5>3?03@/?/<@B2BA2/<>/<8/<5A3:[email protected]=>B<AB9/ >3<55B<//<<=?;/:0 0/E/<5/</967?<E/;/E/E/<52703<AB9 1;2/?7:3<@/=9B:3? *30B/69/;3?/23<5/<4=9B@ ;;/D/:<E/275B</9/<B<AB9;3<5/;07:5/;0/?@30B/603<2/>/2/8/?/9 ;2/?7:3<@/#3;B27/<9/;3?/[email protected]275B</9/<B<AB9;3<5/;07:5/;0/?@30B/603<2/E/<5A3?:3A/91B9B>8/B6/ 3?/>/8/B69/6:3<@/9/;3?/6/?B@[email protected]?0 #3;/</9/6/?/6>3?53@/?/<:3<@/9/;3?/[email protected]%1*!+!.,!($!,!-"4+4,!3)(!.

144Mudah dan Aktif Belajar Fisika untuk Kelas X@3>3?A7@74/A@74/A<E//>/A7>/<AB:9/<!(!6!/>/A707/@9/<=:36=:36J 3?;7</A/?J 3?;7<39B<5J 3?;7<3;0B<5J $3<@/39B<5J $3<@/3;0B<5J (?7@;/2783:/@9/<2/:/;J+3=?7(/?A793:J +3=?73:=;0/<527A3?/>9/<:/A:/A'>A79$B>%/A/+3?=>=<5%[email protected]=>#/;3?/;3;7:7971=<A=6<E/2/>/A;3<23?7A/%/A//1/AJ %7=>7J ([email protected]=>7J @A75;/A7@;/J /E/9=;=2/@7J +7A7939/A "!" %" 1;J +7A79"/B6 "!"!"Peta KonsepSetelah mempelajari bab ini, tentu Anda dapatmenyebutkan dan menganalisis alat-alat optik sepertimata, lup, mikroskop, teropong dan kamera. DapatkahAnda menyebutkan alat-alat optik lainnya? Adakahmateri dalam bab ini yang Anda anggap sulit? Agar semuamateri dalam bab ini dapat Anda pahami, cobalahdiskusikan dengan teman Anda atau minta penjelasankepada guru.Refleksi

145Cahaya dan Optika ),)(,!(2!,!(2!34*!5!"!.6!.'0!,).'3%0!3$!.+%1*!+!.,!(0!$!"4+4,!3)(!.-4 *303?9/@@7</?;3<53</7@[email protected];=>A79E/<5A3?27?7/A/@2B/13?;7<2/A/?E/<5@/:7<5A35/9:B?B@*3A3:/603?9/@@7</?;3<5/:/;7>3;/<AB:/<2B/9/:7/?/603?9/@@7</?/ ;3<B8B@7</?2/A/<50 ;3;=A=<5@7</?2/A/<51 A35/9:B?B@@7</?2/A/<52 @38/8/?2/<03?:/D/</</?/6@7</?2/A/<53 @38/8/?2/<@3/?/623<5/<@7</?2/A/<5 *3=?/<5D/<7A/@3A7<557 ;03?27?72723>/<13?;7<2/A/?C3?A79/:+7<557;7<7;B;13?;7</5/?7/2/>/A;3:76/A0/E/<5/<@3:B?B6AB0B6<E//<2/79/<>[email protected]@7;/A/D/<7A/[email protected] 1;270/D/60/57/</A/@93>/://2/:/6/ 1;2 1;0 1;3 1;1 1; (3?6/A79/<5/;0/?03?79BA/ 1;2 1;0 1;3 1;1 1; *B/AB@7</?2/A/<5>/2/>3?;B9//<9/1/23<5/<@B2BA2/A/<593;B27/<2707/@9/<23<5/<@B2BA07/@*7</?07/@[email protected];3<5/:/;723C7/@7@303@/?/2 IK0 7K3 IK1 IK *303?9/@@7</?;3?/;0/A2/?7;327B;E/<57<239@07/@<E/93;327B;@3>3?A75/;0/?/;0/?[email protected];3;>3?:76/A9/<@3=?/<5>3<5/;/A03?27?72723>/<13?;7<2/A/?@38/B6%;5/?7/2/>/A;3:76/A@3:B?B6:30/?27<27<5E/<503?/2/2703:/9/<5<E/;/9/<7:/7%;/[email protected];B;/2/:/6/ 1;2 1;0 1;3 1;1 1; *30B/603<2/27:3A/99/< 1;2723>/<13?;7<13;0B<5E/<58/?/94=9B@<E/ 1;$3A/92/<@74/A0/E/<5/<E/<52703<AB9=:3613?;7<[email protected]/2/:/6/ 1;2723>/<13?;7<;/E/A35/90 1;2703:/9/<513?;7<<E/A/A35/91 1;2723>/<13?;7<<E/A/A3?0/:792 1;2703:/9/<513?;7<;/E/A35/93 1;2723>/<13?;7<<E/A/A35/9 /E/<5/<;/E/E/<5A3?03<AB9=:36@30B/613?;7<139B<5A75/9/:7:307603@/?2/?7>/2/03<2/<E/"79/8/?/94=9B@13?;7< 1;8/?/903<2/2723>/<13?;7</2/:/6/ 1;2 1;0 1;3 1;1 1; "79/0/E/<5/<E/<5A3?03<AB9=:3613?;7<139B<523<5/<8/?78/?793:3<59B<5/< 1;/2/:/6<E/A/2/<27>3?03@/?2B/9/:703<2/<E/A3?:3A/927;B9/13?;7<@38/B6n1n2B(3?<E/A//<E/<503</?/2/:/6/@7<%@7<0@7<@7<%11=@1=@%21=@%1=@3@7<%1=@ (/2/>3;07/@/<1/6/E/2/?7B2/?/93/7?@3;/97<9317:@B2BA2/A/<5/ @3;/97<03@/?@B2BA07/@0 @B2BA07/@A3A/>@/8/1 @3;/97<9317:>B:/@B2BA07/@2 @B2BA07/@@3;/97<03?5/<AB<5>/2/7<239@07/@3 @B2BA07/@2/>/A;3<8/279317:/A/B03@/?03?5/<AB<5>/2/>=:/?7@/@71/6/E/ *303?9/@1/6/E/2/A/<52/?7;327B;93;327B;23<5/<@B2BA2/A/<5 I2/<2707/@9/<23<5/<@B2BA@303@/?I!<239@07/@?3:/A74;327B;A3?6/2/>;327B;/2/:/6/203 1 "79/1/6/E/;=<=9?=;/A7@;3;/@B97;327B;E/<503?7<239@07/@:307603@/?>/<8/<553:=;0/<5%2/<9313>/A/<#03?B0/6@30/5/703?79BA(3?<E/A//<E/<503</?/2/:/6/%2/<#;3<8/27:307603@/?0%2/<#;3<8/27:30769317:1%;3<8/27:307603@/?2/<#;3<8/279317:2%;3<8/27:30769317:2/<#;3<8/27:307603@/?3%2/<#A3A/>x2 m1m2m16 mpengamat5 mxTes Kompetensi Bab 6

146Mudah dan Aktif Belajar Fisika untuk Kelas X /6/E/;3;7:7979313>/A/<272/:/;C/9B;@303@/? L ; @"79/;/@B9932/:/;/7?9313>/A/<;3<8/27 13?/?A77<239@07/@/7?7AB/2/:/6/ 2 0 3 1 "79/>/2/>3?;B9//<F/A1/7?7<239@07/@278/AB69/<@7</?;=<=9?=;/A7@23<5/<>/<8/<553:=;0/<5 H2/<@B2BA2/A/<5 I;/9/@7</?E/<52707/@9/<272/:/;F/A1/7?;3;7:797>/<8/<553:=;0/<5/ H2 H0 H3 H1 H *303?9/@1/6/E/23<5/<>/<8/<553:=;0/<5 L K1;;/@B92/?7B2/?/932/:/;0/:=99/1/E/<57<239@07/@<E/(/<8/<553:=;0/<51/6/E/272/:/;9/1/[email protected]/2/:/6/ L K1; 2 L K1;0 L K1; 3 L K1;1 L K1; /:/;A/0B<5E/<5[email protected]3A3?7<239@07/@ 8/?/9/<A/?/>3?;B9//<1/7?/<23<5/</:/@A/0B<5<E//2/:/61;"79/<2/;3;/<2/<5@31/?/A35/9:B?B@2/?7>3?;B9//<8/?/9/<A/?//:/@A/0B<52/<>3?;B9//<1/7?/<;3<8/27/ 1;2 1;0 1;3 1;1 1; *30B/60/E/<5/<A3?03<AB9>/2/8/?/9;2703:/9/<5:3<@/E/<503?939B/A/<27=>A?7$3A/903<2/A3?6/2/>:3<@/[email protected]/2/:/6/ ;2 ;0 ;3 ;1 ; *30B/6:3<@/27B2/?/;3;7:7978/?/94=9B@1;!<239@07/@0/6/<:3<@/(/2/@//A:3<@/03?/2/272/:/;/7?E/<57<239@07/@<E/348/?/94=9B@:3<@/;3<8/27/ 1;2 1;0 1;3 1;1 1; "79/2B/0B/6:3<@/A7>7@E/<503?8/?/94=9B@K1;2/< 1;275/0B<59/<939B/A/<:3<@/5/0B<5/<2/:/;27=>A?7/2 K0 K 3 1 +75/0B/6:3<@/;/@7<5;/@7<5;3;7:7978/?/94=9B@ 1;K 1;2/< 1;*B;0B@B;0B=>A79<E/A3?:3A/9>/2/@/AB5/?7@:B?B@"/?/9/<A/?/@/AB:3<@/2/<:3<@/E/<5:/7<;/@7<5;/@7<51;"79/@7</?;/A/6/?7;3;/@B97:3<@/>3?A/;/@3>/<8/<5@B;0B=>A79<E/;/9/0/E/<5/<;/A/6/?7E/<52703<AB9=:36@[email protected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email protected]03?/2/ 1;2/?727<27<5/9B/?7B;2/<@[email protected]=?/<503?27?7>/2/8/?/9 1;2/?727<27<5[email protected]/ 7;/</0/E/<5/<79/<E/<527:76/A=?/<50 7;/</0/E/<5/<=?/<5E/<527:76/A79/< *30B/6:3<@/13;0B<5?/<59/>;3;7:7978/?78/?793:3<59B<5/< 1;2/< 1;A3?0B/A2/?753:/@ 7AB<5:/68/?/94=9B@2/<939B/A/<:3<@/