Jawabanmu

2014-05-25T19:03:41+07:00
Em1=Em2
mgh1=mgh2 + 1/2mv^{2}  (m bisa dicoret hingga habis)
10x15 =  10x7 + 1/2x v^{2}
v^2= 160
v=4
5 4 5