An iron boiler of mass 180 kg contains 730 kg of water at 11 ∘C.A heater supplies energy at the rate of 58,000 kJ/h. The specificheat of iron is 450 J/kg⋅C∘, the specific heat of water is 4186J/kg⋅C∘, the heat of vaporization of water is 2260 kJ/kg⋅C∘. Assumethat before the water reaches the boiling point, all the heatenergy goes into raising the temperature of the iron or the steam,and none goes to the vaporization of water. After the water startsto boil, all the heat energy goes into boiling the water, and nonegoes to raising the temperature of the iron or the steam.
How long does it take for the water to reach the boiling pointfrom 11 ∘C∘C?
How long does it take for the water to all have changed to steamfrom 11 ∘C∘C?
