Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components on one side as shown in the figure. The board is placed in a room at 20°C. The heat loss from the back surface of the board is negligible. The surface temperature of circuit board is 46°C. Determine the total heat loss by convection and radiation if the board is vertical, Take the emissivity of the surface of the board to be 0.8 and assume the surrounding surfaces to be at the same temperature as the air in the room. (Answers: 8W) Hint: The properties of the air at latm. are as follow: k = 0.02607 W/m. C v =1.631x10 m³/s Pr = 0.7275 Insulation PCB, T, L= 0.2 mh Air T = 20°C

Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components on one side as shown in the figure. The board is placed in a room at 20°C. The heat loss from the back surface of the board is negligible. The surface temperature of circuit board is 46°C. Determine the total heat loss by convection and radiation if the board is vertical, Take the emissivity of the surface of the board to be 0.8 and assume the surrounding surfaces to be at the same temperature as the air in the room. (Answers: 8W) Hint: The properties of the air at latm. are as follow: k = 0.02607 W/m. C v =1.631x10 m³/s Pr = 0.7275 Insulation PCB, T, L= 0.2 mh Air T = 20°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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