Jawabanmu

2014-02-21T19:20:58+07:00
Ep₁ = m₁ . g . h₁
400 J = 5 kg . 10 m/s² . h₁
 \frac{400 J}{5kg . 10m/s²} = h₁
8 m = h₁

h₂ = 2h₁
    = 2 . 8 m
    = 16 m

Ep₂ = m₂ . g . h₂
400 J = m₂ . 10m/s² . 16 m
 \frac{400 J}{16 m . 10 m/s²} = m₂
2,5 kg = m₂
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