Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning - Discussion

14. 

Fourier's law of heat conduction is (where Q = Amount of heat flow through the body in unit time, A = Surface area of heat flow, taken at right angles to the direction of heat flow, dT = Temperature difference on the two faces of the body, dx = Thickness of the body, through which the heat flows, taken along the direction of heat flow, and k = Thermal conductivity of the body)

[A].
[B].
[C].
[D].

Answer: Option A

Explanation:

No answer description available for this question.

Rayudu Babu T.C said: (Aug 12, 2013)  
Rate of heat exchange is directly proportional to temperature gradient.

Swapnil said: (Aug 15, 2013)  
Thermal conductivity of material is taken as negative (-ve sign should be there) because heat always flow from higher temperature to lower temperature, so the value of temperature gradient is negative, amount heat flow is always positive value.

Avaneesh said: (Dec 30, 2013)  
Yes ! SWAPNIL is right. The formula must contain a negative sign.

Rama Krishna said: (Mar 29, 2014)  
Rate of heat flux is directly proportional to temperature gradient.

Suzer said: (Sep 10, 2019)  
Here dt/dx indicates the temperature difference so it can be + or -.

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