A silicon wafer of diameter D120 mm, and emissivity of 0.6 is at an initial temperature of Ti 325oC and is allowed to cool in quiescent, ambient air and large surroundings for which Tair Tsur 350C. What is the rate of cooling from the upper surface of the wafer? Properties of Air: k- 0.0373 W/m.C. v32.39*10-6 m2/s, alpha 47.210-6 m2s Pr 0.686. B- 1/Tf = 0.0022 K-1. Select one: O a. 344 W O b. 53 W O . 627 W O d. 86 W

A silicon wafer of diameter D120 mm, and emissivity of 0.6 is at an initial temperature of Ti 325oC and is allowed to cool in quiescent, ambient air and large surroundings for which Tair Tsur 350C. What is the rate of cooling from the upper surface of the wafer? Properties of Air: k- 0.0373 W/m.C. v32.39*10-6 m2/s, alpha 47.210-6 m2s Pr 0.686. B- 1/Tf = 0.0022 K-1. Select one: O a. 344 W O b. 53 W O . 627 W O d. 86 W

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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