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A wall of thickness 0.6 m and thermal conductivity 0.6 W / m-K has a surface area of 1 m2. If the inner and outer temperature of the wall are 1840°C and 340°C, respectively, the rate of heat transfer will be:

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  1. 150 W
  2. 75 W
  3. 750 W
  4. 1500 W

Answer (Detailed Solution Below)

Option 4 : 1500 W

Detailed Solution

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Concept:

Fourier law of heat conduction:- 

Calculation:

Given:

b = 0.6 m, k = 0.6 W/mK, A = 1 m2, Ti = 1840°C, To = 340°C 

Q = 1500 W

Heat conduction throw a hollow cylinder

 

Heat conduction throw a hollow sphere

 

 

 

 

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