Termodinamika
183
,6;E=2982C52=2BE2?8D6BDEDEAF=E6?H2
=:D6BD62?2?2D52?CE9E?H2 L 2CD6BC63ED5:A2?2C2?56?82?D62?2?D6D2AC69:?8826?42A2:CE9EL
-6?DE2?F=E682C52?EC292H2?85:=2E2?82CD6BC63ED 7
:6D29E: ,2D
=:D6B 2
6BC222?82CA252D62?2?D6D2A252=29 =:D6B
=:D6B C69:?882F=E682C6?;25:=:D6B
3 ,
O O
;E=6
d. Proses Adiabatik
BC6C 25:232D: 252=29 ABC6C A6BE3292? 62522? C:CD6 D2?A2 252?H2 A6BDE2B2? 2=B 56?82? =:?8E?82??H2 2D2E D:52 252 2=B
H2?8 5:=6A2C 2EAE? H2?8 5:D6B:2 =69 82C D6BC63ED C69:?882 B27:A252.26?E?;E2?329G2A252ABC6C25:232D:
D6B;25:A6BE3292?CE9ED62?2?52?F=E6BC6C:?:36B52C2B2? -00.
+..+ H2?8 5:DE=:C2? , ?CD2? 2D2E
, ,
O 52?
D6D2A 2D2E O
6?82? 252=29 +. , H2?8 6BEA22? A6B32?
5:?82?2A2C:D2C2=B82CA252D62?2?D6D2A
A
52?2A2C:D2C2=B82C A252 F=E6 D6D2A
F
,642B2 2D62D:C 36C2B2? D6BC63ED 5:DE=:C
A F
:32D D:52 252?H2 A6BDE2B2? 2=B 56?82? =:?8E?82? EC292 H2?8 5:=2E2? =69 82C 92?H2 6?8E329 6?6B8: 52=2 6C2B?H2 EC292
D6BC63ED 52A2D 5:D6?DE2? 56?82? 6BE;E 23. 9
C69:?882 5:A6B=69 A6BC222?
, O
, O
2D2E O
O .C292 H2?8 5:=2E2? =69 82C A252 ABC6C 25:232D: 52A2D 5:A6B=69
56?82? 6?88E?22? 23. 9 52? 23. 9
;:2 62522? 2G2= 52? 62522? 29:B 5:6D29E: ?D9 ABC6C 25:232D: 52=2
69:5EA2? C692B:92B: 252=29 A6E2:2? 82C A2?2C A252 6C:? 5:6C6= 52? 6C:? A6?5:?8:?
Gambar 8.8
Grafik p–V pada proses adiabatik lebih curam daripada proses
isotermal. V
p proses
adiabatik proses
isotermik p
2
p
1
V
1
V
2
Contoh
8.4
2C:562=6?82=2:6CA2?C:C642B225:232D:E=2E=236C2BD62?2?82C252=29 P
2,6D6=296CA2?C:D62?2?82C6?;25: 2-6?DE2?F=E682C29:B
;:2F=E682CE=2E=2 C6BD2?CD2?D22A=246
Contoh
8.5
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
