Jawabanmu

2014-05-06T12:35:19+07:00
M1 . C1 . ( Tt - Tc ) = M2 . C2 . ( Tc-Tr)
1.4200.(90-Tc)=1.4200.(Tc-60)
4200.(90-Tc)=4200.(Tc-60)
378 KJ - 4200 Tc = 4200 Tc - 252 KJ
378 + 252 KJ = 4200 + 4200 Tc
630000 : 8400 = 75 celcius
1 5 1
2014-05-06T18:22:29+07:00
Qlepas=Qterima
m1x(T1-T)=m2x(T-T2)
1x(90-T)=2(T-120)
90-T=2T-120
90+120=2T-T
210=3T
70°C=T