An electric fan has the motor inside a sphere of 25 cm diameter, which a uniformly distributed gives heat source of 2500 W/m . A three blades of 50 cm long and 3 mm thickness and 15 cm wide are welded to the surface of the sphere. The convective heat transfer coefficient between the air and the blades is 15 Wmit,and the thermal conductivity of the sphere and the blade is 8 Wmic, and the ambient temperature is 5 c. What is the temperature of the blade at 35 cm from the sphere, and the heat transferred by the three blades.

An electric fan has the motor inside a sphere of 25 cm diameter, which a uniformly distributed gives heat source of 2500 W/m . A three blades of 50 cm long and 3 mm thickness and 15 cm wide are welded to the surface of the sphere. The convective heat transfer coefficient between the air and the blades is 15 Wmit,and the thermal conductivity of the sphere and the blade is 8 Wmic, and the ambient temperature is 5 c. What is the temperature of the blade at 35 cm from the sphere, and the heat transferred by the three blades.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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