Jawabanmu

2014-03-17T22:08:01+07:00
Energi Kinetik = 1/2mv^2
m = 200 mg = 200.10^-6
v = 72 km/jam

Ek = 1/2 mv^2
= 1/2 x 200.10^-6.(72)^2
= 100.10^-6.5184
=5184.10^-4

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