źródło:
1 l = 1 kg m = 1 kg T1 = 25 C T2 = 200 C delta t = T2 - T1 delta T = 100 C - 25 C = 75 C cw = 4200 J/kg * C
E = m * cw * delta t E = 1 kg * 4200 J/kg * C * 75 C E = 315000 J = 315 kJ ; kilo = 1000