A piece of iron of mass 0.2 kg is kept inside a furnace, till it attains the temperature of the furnace. The hot piece of iron is then dropped into a calorimeter containing 0.24 kg of water at 20 °C. The mixture attains an equilibrium temperature of 60 °C. The temperature of the furnace is
506.80 oC
Let θ1 be temperature of the furnace that is temperature of the piece of iron.
Thus, the heat lost by piece of iron is
Q = M1C1 (θ1 - θ)
= 0.2 x 470 (θ1 - 60) = 94 (θ1 - 60)
Heat gained by water and calorimeter is
Q = (M2 + w) x c2 x (θ - θ2)
= (0.24 + 0.01) x 4200 x (60 - 20) = 42000
From above two equations
94 (θ1 - 60) = 42000
θ1 = 506.80 oC