Mudah dan Aktif Belajar Fisika untuk Kelas XI
192
6?EBED =2EC:EC 6C:? C6=2=E 66B=E2? EC292 =E2B 282B 52A2D 6:?5292? 2=B 52B: D6A2D H2?8 36BCE9E B6?529 6 D6A2D H2?8
36BCE9ED:?88:6C:?C6A6BD::?:5:C63ED6C:?A6?5:?8:?:C2=?H2=62B: 6C 52? A6?5:?8:? BE2?82? 2D2E
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1. Proses Reversibel dan Irreversibel
BC6CABC6CA2526C:?2=B252H2?836BC:72D -1-.52?252AE=2
H2?8 36BC:72D --1-. D:52 B6F6BC:36= BC6C -1-. 6BEA22?
ABC6CH2?836B=2?8CE?8C2?82D=232DC69:?882ABC6C?H252A2D5:2?882A C63282: B2?82:2? 62522? C6D:32?8 ,6=EBE9 ABC6C D6BC63ED 52A2D
5:6B;22?C642B2632=:2?D2?A26?8E32936C2BEC292H2?85:=2E2? 2D2E 2=B H2?8 5:A:?5292?
BC6CB6F6BC:36=C6AEB?2D:5252A2D5:D6?DE2?52=26?H2D22?2B6?2 ABC6C:?:D2D6B32D2CBC6C:?:;E826?896?52:D:52252?H286C62?
82?88E2? 2=:B2? E52B2 C6BD2 72DB A6?8E329 2=B 52? EC292 =2:??H2 BC6C H2?8 252 A252 6?H2D22??H2 252=29 ABC6C :BB6F6BC:36= 252
ABC6C ?H2D2 :C2=?H2 2C:9 5:D6E2? 86C62? H2?8 6?H63232? 252?H2 A2?2C H2?8 9:=2?8 2D2E 2=:B2? 82C H2?8 36BE329
2. Mesin Pendingin Refrigerator
EE-6B5:?2:236BA682?86A252646?56BE?82?2=2:29 C:72D2=BH2?8C6=2=E6B232DC642B2CA?D2?52B:36?5236BCE9ED:?88:
636?52H2?836BCE9EB6?52964E2=:;:2252EC292=E2BH2?862C2 6:?5292? 2=B 52B: C:CD6 36BCE9E B6?529 6 =:?8E?82? H2?8
36BCE9E =63:9 D:?88: 252 6C:? A6?5:?8:? C:CD6 6?823:= 2=B
52?6=6A2C2?2=B 52AE?EC292H2?85:=2E2?252=29
,:=EC 6C:? A6?5:?8:? 52A2D 5:=:92D A252 .2
6D6B2?82? 8232B 2=B H2?8 5:=6A2C2? A252 CE9E D:?88:
2=BH2?85:C6B2AA252CE9EB6?529 EC292 H2?8 5:=2E2? 52B: =E2B
.EB2? 52H2 C63E29 6C:? A6?5:?8:? 5:?H2D22? 56?82? 67:C:6? 52H2 8E?2 ,642B2 2D62D:C 52A2D 5:DE=:C2? C63282: 36B:ED
O 62B:6C52?A6?5:?8:?BE2?82?6:=::67:C:6?52H28E?252=2
;2?82E2?C2A2:56?82?,62:?D:?88:?:=2: C62:?32:6C:?
A6?5:?8:? D6BC63ED
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T
1
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2
Gambar 8.15
Perubahan kerja menjadi kalor.
Tantangan
untuk Anda
Mengapa AC menggunakan freon? Apakah freon dapat
digantikan oleh gas lain?
-6A6B2DEB5:52=2C63E29=62B:6C252=29O
L=E:526B;2H2?85:2A2D2? 5:52=2?H26?8632?8A252D6A6B2DEBC636C2BL-6?DE2?=2967:C:6?
52H28E?2=62B:6CD6BC63ED 7
:6D29E: O
6?82?6?88E?22?A6BC222?
Contoh
8.9
Termodinamika
193
,E9E5:52=2C63E29=62B:6C252=29OL=E:52 6B;2H2?85:2A2D2?5:52=2?H26?863E?
A252CE9EL-6?DE2?=2967:C:6?52H28E?2 =62B:6CD6BC63ED
,6;E=2922?2?52=2=62B:6C6?892C:=2? 2=BC636C2B
:267:C:6?52H28E?2=62B:
6C D6BC63ED
-6?DE2?=29 6?6B8: =:CDB: H2?8 5:A6B=E2?=62B:6CE?DE6:?5292?2=BH2?8
5:92C:=2?22?2?
6C:?A6?5:?8:?BE2?82?6?H6B2A2=BC636C2B 52=2 G2DE C6? ,E9E BE2?82?
5:A6BD292?2? C636C2B L C652?82? CE9E
Tes Kompetensi Subbab
D
2+,--.5,5-4 =:?8E?82?D6A2DA63E2?82?2=B252=29
L
-6?DE2?=2952H2=:CDB:H2?85:3EDE92? ,E2DE6C:?A6?5:?8:?36B52H26B;2
G2DD:2
CE9EBE2?8A6?5:?8:?OL52?CE9EE52B25:=E2B L2?882A6C:?:562=36B2A22=B2C:E
H2?8 52A2D 5:C6B2A 6C:? A6?5:?8:? 52B: BE2?8 A6?5:?8:??H2C6=22
6?:D
,E2DE32?8E?2?96?525:5:?8:?2?56?82?C63E29 6C:?A6?5:?8:?:562=,E9E5:=E2B32?8E?2?L52?
5:52=232?8E?2?L:22=2DA6?5:?8:?D6BC63ED 36B6E2D2?
,,G2DD36B2A2A2?2CH2?8 5:6=E2B2?52B:32?8E?2?D6BC63EDC6D:2A;2
Rangkuman
2=B6BEA22?C2=29C2DE36?DE6?6B8:H2?852A2D 36BA:?52952B:CE2DE=:?8E?82?6CE2DEC:CD62D2E
C632=:?H22=B36BA:?52952B:CE9ED:?88:6CE9E H2?8=63:9B6?529
25262522?D62?2?D6D2AEC292H2?85:=2E2? 82C252=29
,
, O
, :282C6=2E2?6CA2?C:A6?8632?82?EC292
36B?:=2:AC:D:7H2?86?H63232?F=E636BD2329 2D2E
:2 82C 5:2A2D2? EC292 36B?:=2: ?682D:7 :?8E?82?6=2E2?EC292A252C:CD6C69:?882
2CH2?836B25252=2BE2?8D6BDEDEA52A2D5:E329 62522??H26=2=E:3636B2A2ABC6C
2 BC6CCD6B2=D6B;25:A252CE9ED6D2A.C292 H2?85:=2E2?82C252=29
=? 3 BC6CC9B:D6B;25:A252F=E6D6D2A.C292
H2?85:=2E2?82C252=29 ,
4 BC6CC32B:D6B;25:A252D62?2?D6D2A.C292 H2?85:=2E2?82C252=29
, O
, 5 BC6C5:232D:D6B;25:A25262522?C:CD682C
D:52 6?82=2: A6BDE2B2? 2=B 56?82? =:?8E?82?252ABC6C:?:D6B;25:A6BE3292?CE9E
D62?2?52?F=E6.C292H2?85:=2E2?82C 252=29
O EE-6B5:?2:25:BEEC2?C63282:36B:ED
,6;E=292=BH2?85:36B:2?6A252C:CD65:A22: C6328:2? =69 C:CD6 E?DE 6=2E2? EC292
,6=:C:96?6B8: OC2256?82?A6BE3292?6?6B8:
52=2 52B:C:CD6H2:DE
2A2C:D2C2=B52B:CE2DEI2D5:567:?:C:2?C63282: 32?H2?H22=BH2?85:A6B=E2?E?DE6?2:2?
CE9EI2DD6BC63EDC636C2BC2DE6=F:?2D2EC2DE56B2;2D 46=C:EC
2A2C:D2C2=BE?DEABC6C:C9B: 1D6D2A
2A2C:D2C2=BE?DEABC6C:C32B: ,D6D2A
A
E3E?82?2?D2B2
A
56?82?
F
252=29
A
O 252C:=EC2B?D82C6?6B:22=B
52B:B6C6BF:B 36BCE9ED:?88:52?6=6A2C2=B
6B6C6BF:B36BCE9E B6?529,:=EC2B?D6BEA22?52C2B52B:6C:?5:6C6=
6C:?2B?DH2:DE6C:?H2?8A2=:?8:562= 7:C:6?C:6C:?6BEA22?A6B32?5:?82?2?D2B236C2B
EC292H2?852A2D5:=2E2?=69C:CD6D6B9252A2=B H2?85:C6B2A
5:A6B=69
25:67:C:6?52H28E?2=62B:6CD6BC63EDC636C2B
