Hot water at average temperature of 90°C is flowing through a cast iron pipe (k=40 W/mK) whose inner and outer diameters are 3 cm and 4.5 cm, respectively. The pipe is insulated with 3 cm thick fiberglass insulation (k=0.04 W/mK). The outer surface of the pipe is exposed to the air at 20°C in the basement, with a heat transfer coefficient of 20 W/m²K . The heat transfer coefficient at the inner surface of the pipe is 100 W/m2K. What is the inner surface temperature? E a. 38 °C O b. 88 °C O c. 79 °C O d. 13 °C O e. 23 °C

Hot water at average temperature of 90°C is flowing through a cast iron pipe (k=40 W/mK) whose inner and outer diameters are 3 cm and 4.5 cm, respectively. The pipe is insulated with 3 cm thick fiberglass insulation (k=0.04 W/mK). The outer surface of the pipe is exposed to the air at 20°C in the basement, with a heat transfer coefficient of 20 W/m²K . The heat transfer coefficient at the inner surface of the pipe is 100 W/m2K. What is the inner surface temperature? E a. 38 °C O b. 88 °C O c. 79 °C O d. 13 °C O e. 23 °C

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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