Jawabanmu

2014-06-04T18:55:23+07:00
2x4200x(75-25)= 2 x 4200 x 50
Q = 420000 joule = 420 kj
2014-06-04T18:57:16+07:00
Diket :
m = 2 kg
t awal = 25 derajat Celcius
t akhir = 75 derajat celcius
C air = 4200 J/kg
Ditanya : Q ?
Jwb:
Q = m.c.ΔT
   = 2.4200.50
   = 420.00 J

Semoga membantu ^^