Q2.3 Solar houses are designed to retain the heat absorbed during the day so that the stored hear can be released during the night. A botanist produces steam at 100- during the day and then allows the steam to cool to 0 °C and freeze during the night. How many kilograms of water are needed to store 200 kJ of energy for the process? (Use the laten heat of vaporization of water L. = 22.6 × 105 3/ Kg, the laten heat of fusion of water L₁= 33.5 x 104 J/Kg, and the specific heat capacity of water c = 4186 J/ kg. C. Hint: you need to use both the formula of the heat Q = mcVT and Q = mL)

Q2.3 Solar houses are designed to retain the heat absorbed during the day so that the stored hear can be released during the night. A botanist produces steam at 100- during the day and then allows the steam to cool to 0 °C and freeze during the night. How many kilograms of water are needed to store 200 kJ of energy for the process? (Use the laten heat of vaporization of water L. = 22.6 × 105 3/ Kg, the laten heat of fusion of water L₁= 33.5 x 104 J/Kg, and the specific heat capacity of water c = 4186 J/ kg. C. Hint: you need to use both the formula of the heat Q = mcVT and Q = mL)

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter2: Matter And Energy

Section: Chapter Questions

Problem 27RQ: How many Btu/h would be produced in a 12-kW electricheater?

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