Se dă:
m1= 300g = 0,3kg apă
°t1 = 0°C
m2 = 200g = 0,2kg - bila de fier
°t2 = 100°C
c1 = 4185 J/kg*K
c2 = 459,8 J/kg*K
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t= ?
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[tex] Q_{ced}=Q_{prim} \\
m1*c1 *(t-t1)= m2*c *(t2-t) \\
[/tex]
0,3kg *4185J/kg*K (°t-0°C)= 0,2kg * 459,8 J/kg*K * (100°C - t)
1255,5 * (°t-0°C)= 91,96 *(100°C - t)
1255,5 * °t - 0°C = 9196 - 91,96t
1255,5t = 9196 - 91,96t
1255,5t-91,95t = 9196
1163,55t = 9196
t= 9196/1163,55
t = 7,9°C