bagaimana cara no. 18 sampai no. 20?

18. W=FxS
W= 5x13
W= 65 J
20. Ek1=T
V1=V1
V2=3V1
Ek2=......?
T. V1²
___ =
Ek2. ( 3v1)²

9T=Ek2
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