Question

To raise the temperature of 5 kg of water from 20 0C to 30 0C, a 2-kg iron bar is heated and then dropped into the water. What should the temperature of the bar be (ciron = 0.46 kJ/kg 0C)

Answer 1

heat lost by iron + heat gained by water = 0.
[mass Fe x specific heat Fe x (Tfinal-Tinitial)] + [mass H2O x specific heat water x (Tfinal-Tinitial)] = 0
just one unknown,