A long cylindrical power cable is shielded with polyethylene insulation. The power cable is placed in parallel with a long cylindrical metal rod that is maintained at a temperature of 150°C. Both the power cable and the metal rod have the same diameter of 1 cm, and they are inside a blackbody surrounding at 27°C. Their distance apart from each other, measured from their centers, is 20 cm. The emissivity values for the metal rod and the polyethylene insulation are 0.33 and 0.95, respectively. According to the ASTM D1351-14 standard specification, the polyethylene insulation is suitable for operation at temperatures up to 75°C. If the radiation heat transfer per unit area from the metal rod is 445 W/m², determine the surface temperature of the cable and check whether the polyethylene insulation for the power cable would comply with the ASTM D1351-14 standard specification. The surface temperature of the cable is 127.11 > °C. No →, the polyethylene insulation for the power cable will not comply with the ASTM D1351-14 standard specification.

A long cylindrical power cable is shielded with polyethylene insulation. The power cable is placed in parallel with a long cylindrical metal rod that is maintained at a temperature of 150°C. Both the power cable and the metal rod have the same diameter of 1 cm, and they are inside a blackbody surrounding at 27°C. Their distance apart from each other, measured from their centers, is 20 cm. The emissivity values for the metal rod and the polyethylene insulation are 0.33 and 0.95, respectively. According to the ASTM D1351-14 standard specification, the polyethylene insulation is suitable for operation at temperatures up to 75°C. If the radiation heat transfer per unit area from the metal rod is 445 W/m², determine the surface temperature of the cable and check whether the polyethylene insulation for the power cable would comply with the ASTM D1351-14 standard specification. The surface temperature of the cable is 127.11 > °C. No →, the polyethylene insulation for the power cable will not comply with the ASTM D1351-14 standard specification.

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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