Consider an electrically heated room with a floor space of 100 m² and an average height of 4 m at sea level, where the standard atmospheric pressure is 101.3 kPa. Initially the room is at a uniform temperature of 7°C. Now the electric heater is turned on, and it runs until the air temperature in the room rises to an average value of 21°C. Determine the amount of heat transferred (kJ) and the cost of this heat for the following cases. i. The room is air tight and thus no air escapes during the heating process Some air escapes through the cracks at constant pressure ii. The cost of electricity in that area is $0.095/kWh and the gas constant, R=0.287 kJ/kg K. Aloor=100 m2 Patm = 101.3 kPa H = 4 m T1=7°C T2=21°C H Afoor

Consider an electrically heated room with a floor space of 100 m² and an average height of 4 m at sea level, where the standard atmospheric pressure is 101.3 kPa. Initially the room is at a uniform temperature of 7°C. Now the electric heater is turned on, and it runs until the air temperature in the room rises to an average value of 21°C. Determine the amount of heat transferred (kJ) and the cost of this heat for the following cases. i. The room is air tight and thus no air escapes during the heating process Some air escapes through the cracks at constant pressure ii. The cost of electricity in that area is $0.095/kWh and the gas constant, R=0.287 kJ/kg K. Aloor=100 m2 Patm = 101.3 kPa H = 4 m T1=7°C T2=21°C H Afoor

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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