Problem 04.038 Energy balance for an electrical radiator A 40-L electrical radiator containing heating oil is placed in a 50 m³ room. Both the room and the oil in the radiator are initially at 10°C. The radiator with a rating of 2.4 kW is now turned on. At the same time, heat is lost from the room at an average rate of 0.35 kJ/s. After some time, the average temperature is measured to be 20°C for the air in the room, and 70.0°C for the oil in the radiator. Taking the density and the specific heat of the oil to be 950 kg/m³ and 2.2 kJ/kg °C, respectively, determine how long the heater is kept on. Assume the room is well sealed so that there are no air leaks. The gas constant of air is R = 0. 287 kPa m³/kg K (Table A-1). Also, c = 0.718 kJ/kg K for air at room temperature (Table A-2). Oil properties are given to be p = 950 kg/m³ and cp=2.2 kJ/kg. °C (Round the final answer to three decimal places.) Room 10°C Q Radiator ces The heater is kept on for min. •SOLVE IN A HANDWRITTEN FORMAT, DON'T USE CHATGPT.

Problem 04.038 Energy balance for an electrical radiator A 40-L electrical radiator containing heating oil is placed in a 50 m³ room. Both the room and the oil in the radiator are initially at 10°C. The radiator with a rating of 2.4 kW is now turned on. At the same time, heat is lost from the room at an average rate of 0.35 kJ/s. After some time, the average temperature is measured to be 20°C for the air in the room, and 70.0°C for the oil in the radiator. Taking the density and the specific heat of the oil to be 950 kg/m³ and 2.2 kJ/kg °C, respectively, determine how long the heater is kept on. Assume the room is well sealed so that there are no air leaks. The gas constant of air is R = 0. 287 kPa m³/kg K (Table A-1). Also, c = 0.718 kJ/kg K for air at room temperature (Table A-2). Oil properties are given to be p = 950 kg/m³ and cp=2.2 kJ/kg. °C (Round the final answer to three decimal places.) Room 10°C Q Radiator ces The heater is kept on for min. •SOLVE IN A HANDWRITTEN FORMAT, DON'T USE CHATGPT.

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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