Mudah dan Aktif Belajar Fisika untuk Kelas XI
184
,6;6?:C82C36BD62?2?2D36B25252=2G2529 H2?86:=::F=E6
=:D6B:DE?8=29EC292H2?8
5:=2E2?=6982C;:2 2
82C 6E2: A252 D62?2? D6D2A C69:?882 F=E6?H22=:F=E6C6E=252?
3 82C5:2A2D2?A252D62?2?D6D2AC69:?882
F=E6?H2 6?;25: 5E2 A6B D:82 2=: F=E6 C6E=22D
2 -6?DE2?=29EC292H2?85:=2E2?=6982CE?DE
ABC6CC6CE2:56?82?5:28B2 ,636B:ED
Tes Kompetensi Subbab
A
2+,--.5,5-4
3
pPa
V dm
3
7 0 6 0
1 0 200
600 800 A
B
2
pPa 1 4
1 0 A
B
V dm
3
200 500
,63E29D23E?856?82?F=E636B:C:82C:562= 56?82?CE9E
L52?D62?2?
P
2-23E?8 D6BC63ED5:A2?2C2?9:?8826?42A2:CE9E
L
:2F=E6D23E?85:2?882AD6D2A36B2A2D62?2? 82C52=2D23E?8
,E2DE 82C :562= H2?8 F=E6 2G2=?H2 5:6CA2?C:2? C69:?882 F=E6 29:B?H2 6?;25:
A252D62?2?D6D2A
2 2
-6?DE2?=29 EC292 H2?8 5:=2E2? =69 82C D6BC63ED52B:62522?2G2=9:?88262522?29:B
3 ?52:2?ABC6C52A2D5:32=:52B:62522?29:B
662522?2G2=36B2A22936C2BEC292H2?8 5:=2E2?=6982C
.?DE 6A6B64:= F=E6 C63E29 82C 6?;25: C6D6?829?H2C642B2:CD6B2=5:A6B=E2?EC292
6B2A229EC292H2?85:A6B=E2?E?DE6A6B64:= F=E682CD6BC63ED6?;25:C6A6BC6AE=E952B:F=E6
2G2=
,63E296C:?82C=:?6:=::B2C:AB6C:H2:DE B2C:F=E62G2=D6B9252AF=E629:BC636C2B
:2CE9E42AEB2?3292?322BE52B2252=29
L 52? ABC6C AB6C: 36B=2?8CE?8 C642B2 25:232D:
56?82? 36B2A229CE9E42AEB2?3292? 322BD6BC63EDA252AB6C:2C:2=
pPa
Vdm
3
A B
5 0 2 0
200 400 600
4
B. Hukum I Termodinamika
-29E29?52D6?D2?8EE-6B5:?2:2.?DE6?86D29E:?H2 C:2=29 EB2:2? 36B:ED :?: C642B2 C2C22
1. Pengertian Hukum I Termodinamika
EE D6B5:?2:2 6?;6=2C2? 9E3E?82? 2?D2B2 2=B H2?8 5:D6B:2 2D2E 2=B H2?8 5:=6A2C2? =69 C:CD6 6 =:?8E?82? 52? EC292
H2?8 5:=2E2? =69 C:CD6 C6BD2 A6BE3292? 6?6B8: 52=2 H2?8 5:D:3E= 2??H2:C2=2?CE2DEC:CD66?6B:22=B
222=BD6BC63EDD:52 92?H25:8E?22?E?DE6?8E3296?6B8:52=2
D6D2A:;E825:A22: E?DE 6=2E2? EC292
,642B2 6C6=EBE92? 6?6B8: D6BC63ED D:52
7 :6D29E:
, P
2 ,
P 2
6BC222?82CA252ABC6C25:232D:252=29 ,
, 65E2BE2C5:A2?82D2?
C69:?8825:A6B=69
25:F=E682CC6D6=296CA2?C:252=29
Termodinamika
185
252 H2?8 9:=2?8 ?6B8: 52A2D 36BE329 36?DE 6 6?6B8: =2:??H2 52? ;E=29 6?6B8: DD2= C6=2=E D6D2A 6B52C2B2? 9EE 662=2? 6?6B8:
EE -6B5:?2:2 5:BEEC2? C63282: 36B:ED .0 +- 4 - , .. , . +
..0000...-6. ,-0 - - ..
O O2D2E
O .?DE=63:96292:EE-6B5:?2:2D6BC63EDA6B92D:2?
.2
6B;2?;:2? D2?52 E?DE 52? A252 .2 252=29 C63282:
36B:ED 2
:2 C:CD6 6=2E2? EC292 ?:=2: 36BD2?52 AC:D:7
3 :2 C:CD6 6?6B:2 EC292 ?:=2:
36BD2?52 ?682D:7 O 4
:2 C:CD6 6?6B:2 2=B ?:=2: 36BD2?52 AC:D:7
5 :2 C:CD6 6=6A2C 2=B ?:=2:
36BD2?52 ?682D:7 O ?6B8: 52=2 CE2DE 82C :562= 6BEA22? EEB2? =2?8CE?8 52B: CE9E
52? D62?2? 6BE3292? 6?6B8: 52=2 92?H2 36B82?DE?8 A252
62522? 2G2= 52? 62522? 29:B D:52 36B82?DE?8 A252 ABC6C 3282: 2?2 62522? C:CD6 36BE329 .?DE 82C ?2D: 56?82? 56B2;2D
63632C2? A6BE3292?6?6B8:52=252A2D5:9:DE?8C63282:36B:ED
O O
O O
O O
, O
, ,
.?DE 82C 5:2D: 52? A=:2D: 72DB
A252 23. 9 5:82?D: 56?82? 56B2;2D 63632C2? H2?8 5::=:: 82C D6BC63ED
Gambar 8.9
Hubungan sistem dan lingkungan. a Sistem menerima kalor sambil
melakukan usaha. b Sistem melepaskan kalor dan
pada sistem dilakukan usaha. c Sistem menerima kalor, tetapi
tidak melakukan kerja. d Sistem melakukan kerja, tetapi
tidak ada kalor yang masuk ataupun keluar adiabatik.
Q
+
W +
lingkungan sistem
lingkungan
sistem lingkungan
lingkungan Q
W
Q W = 0
Q = 0 W
+ +
– sistem
sistem –
2
3
4
5
,E2DEC:CD66?H6B2A2=B 52B:=:?8E?82?C636C2B
-6?DE2?A6BE3292?
6?6B8:52=2 ;:2
2 C:CD66=2E2?EC292
D6B9252A=:?8E?82?
3 =:?8E?82?6=2E2?EC292
D6B9252AC:CD6
7 2
,:CD66?6B:22=B 52?C:CD66=2E2?EC292
6?EBEDEE-6B5:?2:2 O
O
O
3 ,:CD66?6B:2EC29252B:=:?8E?82?
O
225:A6B=69 O
OO
-2?52AC:D:7E?DE 6?E?;E2?329G26?6B8:52=2C:CD636BD2329
C636C2B
Contoh
8.6
2. Aplikasi Hukum I Termodinamika pada Proses-Proses Termodinamika
,63282:2?2?526D29E:2526A2D;6?:CABC6C52=2D6B5:?2:2 H2:DE ABC6C :CD6B2= :C9B: :C32B: 52? 25:232D: 2=2 3292C2? :?:
22? 5:D6B2A2? EE -6B5:?2:2 A252 ABC6CABC6C D6BC63ED
