please very urgent i need the right answer please be carfully A power transistor of 10 mm of diameter (D),and 15 mm of length (L), is cooled by an airstream with Tair =20 C, and h = 10 W/m^2.K.What is the maximum allowable powerdissipation, Pmax if the surface temperatureshould not exceed 80 C.a.0.3 Wb. 1.8 WО с.4.5 WO d. 3.3 W

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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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A power transistor of 10 mm of diameter (D), and 15 mm of length (L), is cooled by an air stream with Tair =20 C, and h = 10 W/m^2.K. What is the maximum allowable power dissipation, Pmax if the surface temperature should not exceed 80 C. a. 0.3 W b. 1.8 W О с. 4.5 W O d. 3.3 W