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STD 11 - 10.2. transmission of heat — NEET STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 11 - 10.2. transmission of heat4 Marks
Question
Two identical plates of different metals are joined to form a single plate whose thickness is double the thickness of each plate. If the coefficients of conductivity of each plate are $2$ and $3$ respectively, then the conductivity of composite plate will be
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Answer

(b)Thermal conductivity of composite plate
${K_{eq}} = \frac{{2{K_1}{K_2}}}{{{K_1} + {K_2}}} = \frac{{2 \times 2 \times 3}}{{2 + 3}}$$ = \frac{{12}}{5}$= $2.4$

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