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One face of an aluminium cube of edge 2 ...

One face of an aluminium cube of edge `2` metre is maintained at `100^(@)C` and the other end is maintained at `0^(@)C`. All other surfaces are covered by adiabatic walls. Find the amount of heat flowing of heat thorugh the cube in `5` seconds. (thermal conductivity of aliminium is `209 W//m-.^(@)C)`

Text Solution

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Heat will flow from the end at `100^(@)C` to the end at `0^(@)C`. lthrgt Area of cross-section perpendicular to direction of heat flow, A=`4m^(2)` then `(Q)/(t)`=KA`((T_(H)-T_(C)))/(L)`
`Q=((209W//m^(@)C)-(4m^(2))(100^(@)C)(5sec))/(2m)=209kJ`
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