Jawabanmu

2014-09-10T21:12:15+07:00
Dik
Vo =20 m/s
Vt = 40 m/s
t = 4 s
a = ?
s = ?

a = ΔV / Δt
a = 40 - 20 / 4
a = 20 / 2
a = 10 m/s
percepatan setelah 4 sekon = 10 . 4 = 40 m/s

s =  Vo . t + 1/2 .a .t^2
s = 20 . 4 + 1/2 . 5 .4^2
s = 80 + 1/2 . 5 .16
s = 80 + 40
s = 120 meter


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