Respostas

2014-05-24T20:39:49-03:00
90km/h = 25m/s

V = Vo + at
0 = 25 + a*5
-25 = 5a

-25/5 = a

a = -5m/s²

1 5 1
2014-05-25T10:21:42-03:00
V = vo + at

tal que : 

v = 0
vo = 90 km/h = 25 m/s
a = ?
t = 5s

0 = 25 + a5
0 = 25 + 5a
-5a = 25
a = 25/-5
a = -5 m/s²
1 5 1