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STD 11 - 10.2 , transmission of heat — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 10.2 , transmission of heat4 Marks
MCQ
Consider a compound slab consisting of two different materials having equal thickness and thermal conductivities $  K$ and $2K$ respectively. The equivalent thermal conductivity of the slab is
  • A
    $\sqrt {2K} $
  • B
    $3K$
  • ✓
    $\frac{4}{3}K$
  • D
    $\frac{2}{3}K$
✓

Answer

Correct option: C.
$\frac{4}{3}K$
c
(c) $K = \frac{{2{K_1}{K_2}}}{{{K_1} + {K_2}}} = \frac{{2.K.2K}}{{K + 2K}} = \frac{4}{3}K$

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