94
Mudah dan Aktif Belajar Fisika untuk Kelas XI
+85G4;5B?458D4EE4:=4FG;74D8FA::4A
8F8D +8F8?4;8AG5G?4AF4 5B?484AFG?854?58D?4I4A4A78A:4A4D4;E8G?478A:4A8FA::4A
FGA:?4; 4
B8AFG5B?4E858?G74AE8EG74; 8AG5G?4AF4
5 :4J4J4A:758D4A?4AF4C4745B?48F45B?4
8AJ8AFG;?4AF4E8?44
E 2
8F4;G :N
M
: E
-AFG:8D4=4FG;5854E58D?4GC8DE444AE854:458DGF +
1
= +
2
= =
= –
ms =
= ms
4D4;854I4; M 4D4;84F4E
4 +
N
M
:M
EM:
E4D4;AJ4854I4; +
N
M
:
E:
E4D4;AJ484F4E 47 B8AFG 5B?4 E858?G FG5G4A 474?4; M :
E 74A E8F8?4;
FG5G4A474?4;:
E 5
CG?EJ4A:758D4A5B?4 M
MM:
E 4J4J4A:78D=44A?4AF4C4745B?4E8?44
N
M
78F474?4;
:
E E
47:4J4J4A:758D4A?4AF48?4I4A4D4;:8D4=4FG;5B?4
h
1
h
2
Tes Kompetensi Subbab
A
-00
+85G4;5B?4E8C458D4EE4:7F8A74A:;BDKBA F4?B?8;C8A=4:4:4I4A:78A:4A868C4F4A
E
,8AFG4A:4J4J4A:758D4AB?8;4C8A=4:4:4I4A: F8D;474C5B?4=4E8?4A:I4FG48AJ8AFG;5B?4
4
N
M
E 5
N
M
E +8BD4A:EEI48A::8A::45B?458D4EE4:74A
8?8C4D4AAJ4E864D4;BDKBAF4?78A:4A868C4F4A 4I4?
E B?4F8DE85GF858AFGDF4A:E8?44
N
M
EE8;A::458D54?4D4;78A:4A868C4F4A E ,8AFG4A
4 CG?EJ4A:758D4AF4A:C4745B?4
5 :4J4J4A:758D4AF4A:C4745B?474A
6 C8D68C4F4A5B?4C8GG?E8?4458DE8AFG;4A
B. Tumbukan
8DEFI4 FG5G4A 74C4F A74 F8G C474 7G4 58A74 J4A: E4?A: 58DF45D44AE4FGE44?4A 8D4A4AJ4A:84A944F4AE864D4?4A:EGA:
C8DEFI4 FG5G4A 474?4; C8D4A4A 5?4D 74A 5BI?A: ,4;G4; A74 4FGD4A C8D4A4AC8D4A4A F8DE85GF
474 GD44A EG5545 E858?GAJ4 F8?4; 78F4;G 54;I4 CG?E E44 78A:4A C8DG54;4A B8AFG 8DGF A 44A 7=8?4E4A C8DG54;4A
B8AFGJ4A:F8D=47C474E8F4C58A74J4A:E4?A:58DFG5G4AE8DF4 4F4A 4AF4D4 E8F4C C8DG54;4A B8AFG F8DE85GF
Impuls sebanding dengan perubahan momentum.
Ingatlah
Kata Kunci
• impuls • momentum linear
Jika berlaku Hukum Kekekalan Momentum Linear, momentum
linear awal sama dengan momentum linear akhir.
Ingatlah
Contoh
4.1
Momentum, Impuls, dan Tumbukan
95
sebelum tumbukan ketika tumbukan
setelah tumbukan
F
A
v
A
v
B
v
A
v
B
v
A
v
B
Gambar 4.2
Hukum Kekekalan Momentum Linear berlaku pada dua benda
yang bertumbukan.
8D8F474A8D8F4E858?G58DFG5G4A4EA:4EA:8? 4EE4
74A 74A868C4F4A
74A 87G48D8F4F8DE85GF58D474
C474E4FG574A:74F4D74A8?4D4;:8D4J4A:E44 4868C4F4A 8D8F4 ?85; 58E4D 74DC474 868C4F4A 8D8F4 8D8F4 C474 E44F
F8DF8AFG 44A 8A45D4 8D8F4 8F4 8D8F4 8A45D4 8D8F4 E8EG478A:4AGG8IFBA8D8F444A858D4A:4J44E
E858E4D
74A 8D8F4 44A 858D4A :4J4 D84E E858E4D 4:44A4 58E4D :4J4 D84E F8DE85GF C474 8D8F4 4 GG
884?4A B8AFG A84D 58D?4G C474 C8DEFI4 FG5G4A 4AF4D4 8D8F474A58E4D87G4:4J4F8DE85GF44A E4458E4D 4AF8F4C
4D4; 87G4 :4J4 58D?4I4A4A 4D4; E8;A::4 E864D4 4F84FE 74C4F 7FG?E4A E854:4 58DGF
,
4I4?
,
4;D
,
4I4?
,
4I4?
,
4;D
,
4;D
1 1
1 1
M 8F8D4A:4A
1 1
=G?4;B8AFGE858?GFG5G4A
1 1
=G?4;B8AFGE8EG74;FG5G4A BAFB;?4A74DC8DEFI4FG5G4AJ4A:74C4F7?4G4AC8A784F4A
78A:4AGG884?4AB8AFGA84D474?4;C474C8D4A4A 5858D4C4 BF4 58E4D C8D4A4A A 7E85GF =G:4 B5? E8A::B?
B5? F8DE85GF 7:8D44A B?8; 8A8D: ?EFD J4A: 7C8DB?8; 74D =4DA: =4DA:?EFD74F4EAJ4 868C4F4A4EGE8F4CB5?474?4;E444D8A4
8A8D: ?EFD J4A: 7EGC?4 B?8; =4DA:=4DA: ?EFD 7 4F4EAJ4 =G:4 E44 4A F8F4C 58D4F C8AGC4A:AJ4 58D5874 868C4F4A B5? =G:4 58D5874
8F4 F8D=47 58AFGD4A 4AF4D4 7G4 B5? 4F4G ?85; 898 :GA64A:4A J4A: C4?A:8D4E44A7F8D4B?8;B5?78A:4A58D4FC8AGC4A:C4?A:86?
Gambar 4.3
Hukum kekekalan momentum terjadi pada bom-bom car yang
bertumbukan.
Sumber: Dokumentasi Penerbit
E4?AJ44747G45G4;58A74J4A:E4?A:58DFG5G4AE8C8DFC474 - 58DGF
G45G4;8?8D8A:74A4EA:4EA:58D4EE4 :74A:58D:8D4E84D4;78A:4A868C4F4A
E74A
E BEE8?8D8A:75G4FE8784A E8;A::4 8?8D8A: 8AG5G 8?8D8A: 74D
58?44A: +8F8?4; FG5G4A 87G4AJ4 58D:8D4 58DE444A ,8AFG4A 868C4F4A 87G4 8?8D8A:
F8DE85GF
Tes Kompetensi Subbab
B
-00
+8BD4A:A8?4J4A58D4EE4:58D47474F4EC8D4;G : 8D4;G 58D:8D4 78A:4A 8?4=G4A
E
,8AFG4A868C4F4AC8D4;G=4A8?4J4A8?BC4F 78A:4A868C4F4A
E78A:4A4D4;
4
878C4AE84D4;78A:4A4D4;:8D4C8D4;G 5
8 58?44A: 58D?4I4A4A 78A:4A 4D4; :8D4 C8D4;G74A
6 8 E4CA: F8:4 ?GDGE 78A:4A 4D4; :8D4
C8D4;G
A B
A B
v
A
v
B
v
AB
