1-30 A 4-m x 5-m x 7-m room is heated by the radiator of a steam heating system. The steam radiator transfers heat at a rate of 10,000 kJ/h and a 100-W fan is used to distribute the warm air in the room. The heat losses from the room are esti- mated to be at a rate of about 5000 kJ/h. If the initial tempera- ture of the room air is 10°C, determine how long it will take for the air temperature to rise to 20°C. Assume constant specific heats at room temperature. Room 4 mx 6 mx6m Fan FIGURE P1-31 Steam W pw Room 31 5000 kJ/h 4mx5m x 7m FIGURE P1-30 10,000 kJ/h

1-30 A 4-m x 5-m x 7-m room is heated by the radiator of a steam heating system. The steam radiator transfers heat at a rate of 10,000 kJ/h and a 100-W fan is used to distribute the warm air in the room. The heat losses from the room are esti- mated to be at a rate of about 5000 kJ/h. If the initial tempera- ture of the room air is 10°C, determine how long it will take for the air temperature to rise to 20°C. Assume constant specific heats at room temperature. Room 4 mx 6 mx6m Fan FIGURE P1-31 Steam W pw Room 31 5000 kJ/h 4mx5m x 7m FIGURE P1-30 10,000 kJ/h

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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