Airat temperature of 120 °C is contained in a thin-wall steel tube with heat-transfer coefficient 65 W/(m? K). The inside and outside diameters e the tube are 2.5 cm and 2.58 cm, respectively. The thermal conductivity of the steel is 18 W/m K. The tube is exposed to an environment with heat-transfer coefficient 6.5 W/(m K) and temperature 15 °C. Calculate the overall heat-transfer coefficient. O a. 5.9 W/(m K) O b. 9.5 W/(m2 K) Oc. 59 W/(m² K) O d. 95 W/(m? K)

Airat temperature of 120 °C is contained in a thin-wall steel tube with heat-transfer coefficient 65 W/(m? K). The inside and outside diameters e the tube are 2.5 cm and 2.58 cm, respectively. The thermal conductivity of the steel is 18 W/m K. The tube is exposed to an environment with heat-transfer coefficient 6.5 W/(m K) and temperature 15 °C. Calculate the overall heat-transfer coefficient. O a. 5.9 W/(m K) O b. 9.5 W/(m2 K) Oc. 59 W/(m² K) O d. 95 W/(m? K)

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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