Q17 of 27 Page 80

These days people use steel utensils with copper bottom. This is supposed to be good for uniform heating of food. Explain this effect using the fact that copper is the better conductor.

The use of copper with steel in utensils has to do with their different conductivities. The heat transfer depends on the conductivity of the material and is given as:


Here, “H” is the rate of heat transfer, “K” is the thermal conductivity constant, A is the area of cross-section, T2-T1 is the temperature difference.


Copper has higher conductivity and so is heated immediately. Steel on the other hand has lower conductivity. Because of this, the transfer of heat at the intersection of steel and copper is a gradual process. This ensures uniform heating of food.


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