9 A hollow spherical steel has an inner diameter of 30cm and outer diameter of 37cm. It is covered with insulation of 5cm thick. The inner surface of the steel is kept at a constant temperatureof 100°C and outside insulation is 30°C. The thermal conductivity of the material is 0.65 W/m-k. By what percentage will the rate of loss be decreased if the thickness of the insulation isincreased by 4cm?O a. 16.65%O b. 83.35%O c. 79.57%O d. 20.43%O e. None

Given:Inner diameter of sphere, di=30 cmOuter diameter of sphere, do=37 cmThickness of insulation,…

A hollow spherical steel has an inner diameter of 30cm and outer diameter of 37cm. It is covered with insulation of 5cm thick. The inner surface of the steel is kept at a constant temperal of 100°C and outside insulation is 30°C. The thermal conductivity of the material is 0.65 W/m-k. By what percentage will the rate of loss be decreased if the thickness of the insulation is increased by 4cm? O a. 16.65% O b. 83.35% O c. 79.57% O d. 20.43% Qe None

A hollow spherical steel has an inner diameter of 30cm and outer diameter of 37cm. It is covered with insulation of 5cm thick. The inner surface of the steel is kept at a constant temperal of 100°C and outside insulation is 30°C. The thermal conductivity of the material is 0.65 W/m-k. By what percentage will the rate of loss be decreased if the thickness of the insulation is increased by 4cm? O a. 16.65% O b. 83.35% O c. 79.57% O d. 20.43% Qe None

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.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.12P

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A hollow spherical steel has an inner diameter of 30cm and outer diameter of 37cm. It is covered with insulation of 5cm thick. The inner surface of the steel is kept at a constant temperature of 100°C and outside insulation is 30°C. The thermal conductivity of the material is 0.65 W/m-k. By what percentage will the rate of loss be decreased if the thickness of the insulation is increased by 4cm? O a. 16.65% O b. 83.35% O c. 79.57% O d. 20.43% O e. None
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