Put 100 grams of iron on the furnace and heat it for a long time, then take it out. Immediately put 250 grams of water with a temperature of 20 ℃. Finally, the temperature of water rises to 60 ℃. Calculate the temperature of the furnace. (C iron = 0.46 * 10 cubic coke / kg ℃)

Put 100 grams of iron on the furnace and heat it for a long time, then take it out. Immediately put 250 grams of water with a temperature of 20 ℃. Finally, the temperature of water rises to 60 ℃. Calculate the temperature of the furnace. (C iron = 0.46 * 10 cubic coke / kg ℃)

Suppose the mass of iron is m, the temperature change is t, the mass of water is m, the temperature change is t (note the conversion unit is kg). The heat Q emitted by iron is equal to the heat Q absorbed by water, and both of them reach 60 ℃, that is, q = QM * C iron * t = m * C water * t, t = m * C water * t / (m * C iron) is brought into the data, M = 0.1kg, t = 60-20 = 40

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