An electric wire having a diameter of 1.5 mm and covered with a plastic insulation (thickness = 2.5 mm) is exposed to air at 300 K and ho = 20 W/m2.K. The insulation has a thermal conductivity (k) of 0.4 W/m.K. Assuming the wire surface temperature is constant at 400 K and is not affected by the covering a) Calculate the value of the critical radius. b) Calculate the heat loss per meter of wire length with no insulation. c) Calculate the heat loss per meter of wire length with insulation. p.s Could you write the solution clearly? It is hard to understand when written in text. A paper photo with solution would be better. Thanks in advance

An electric wire having a diameter of 1.5 mm and covered with a plastic insulation (thickness = 2.5 mm) is exposed to air at 300 K and ho = 20 W/m2.K. The insulation has a thermal conductivity (k) of 0.4 W/m.K. Assuming the wire surface temperature is constant at 400 K and is not affected by the covering a) Calculate the value of the critical radius. b) Calculate the heat loss per meter of wire length with no insulation. c) Calculate the heat loss per meter of wire length with insulation. p.s Could you write the solution clearly? It is hard to understand when written in text. A paper photo with solution would be better. Thanks in advance

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.68P

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