Page 66 - E-MODUL MODEL CinQASE MATERI GELOMBANG BUNYI DAN CAHAYA KELAS XI_Neat

9. a

Kecepatan ambulans :

v = 72 km/jam = 20 m/s
a
Kecepatam motor

v = ?
m
Keduanya saling menjauhi :

v = 20 m/s dan v bernilai negatif
q m

v − v
f = m × f s
v + v
a
f
v − v = ( + vv )×
m a
f
s
900
340 − v = ( 340 + 20 )×
m
1000
340 − v m = 340× 9 , 0

v = 340 − 324
m
v = 16 m/s
m
v = 57 6 , km/jam
m

10. e

s
v =
t

s E
=
t ρ

5 , 0 20× 10 10
=
t 8000

1
= 2× , 0 0025× 10 6
t

1
= 2× 25× 10 6
t
1
= 2× 5× 10 3
t
1
t = = , 0 0001 s
10 . 000
60