Heat Equation 2D: Conservation of Energy

AI Thread Summary
The discussion centers on the heat equation for a stationary two-dimensional body and the application of the conservation of energy principle. A key point of confusion arises regarding the concept of thickness in a 2D body, as it typically implies a three-dimensional object. The integral equation presented involves a line integral on a closed curve, with thickness denoted in the z-direction, which leads to questions about dimensionality. Clarification is sought on the terminology used, emphasizing that the body is treated as two-dimensional with no variation in the third dimension. Overall, the conversation highlights the need for precise definitions in mathematical contexts.
jahlin
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Homework Statement



heat equation of for 2 dimensional body(stationary)...heat is supplied to a body per unit volume and per unit time and by using conservation of energy principle the following equation is derived..
\intQt dA= \intqt d\ell

the intergral on the right is a line integral on a closed curve.where t=t(x,y) denotes the thickness in the z-direction of the located in the xy - plane.

The Attempt at a Solution


what i don't get is its a 2-dimensional body ..how come it has thickness ?wont it be 3D then ?the graph of a function of 2 variables is a surface without thickness as far i know..
 
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jahlin said:

Homework Statement



heat equation of for 2 dimensional body(stationary)...heat is supplied to a body per unit volume and per unit time and by using conservation of energy principle the following equation is derived..
\intQt dA= \intqt d\ell

the intergral on the right is a line integral on a closed curve.


where t=t(x,y) denotes the thickness in the z-direction of the located in the xy - plane.





The Attempt at a Solution


what i don't get is its a 2-dimensional body ..how come it has thickness ?wont it be 3D then ?the graph of a function of 2 variables is a surface without thickness as far i know..
You will have to explain the question better. Why not give us the whole question exactly as it is worded.

It appears that what they mean by a two dimensional body is simply that there is no variation in the third dimension.

AM
 
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