Jawabanmu

2014-09-03T08:29:11+07:00
Dik :
Vo = 36 km/jam = 10 m/s
Vt = 0
s = 20 m
t = ?

Vt = Vo + a.t
0 = 10 + a .t
a =  \frac{0 - 10}{t}
a =  \frac{-10}{t}

s = Vo.t +  \frac{1}{2} .a.t.t
20 =10.t +  \frac{1}{2} .  \frac{-10}{t} .t.t
20 = 10.t - 5.t
20 = 5.t
t = 20 : 5
t = 4 s


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