Looking for classes? Ksquare Career Institute, Bengaluru →
Thermal Properties of Matter
Conduction: Slabs in Series
1 question from 1 paper, each with its answer.
- question
- 1
- paper
- 1
- of Thermal Properties of Matter
- 2.04%
Concepts tested
- Equivalent conductivity of slabs in series
All Questions
2003 AIPMT 1 question
-
Consider a compound slab consisting of two different materials having equal thicknesses and thermal conductivities K and 2K, respectively. The equivalent thermal conductivity of the slab is -Heat flows through the two layers one after the other, so they are in series. Thermal resistance of a slab: $R = \dfrac{l}{KA}$.
For series connection: $R_{eq} = R_1 + R_2$
$\dfrac{2l}{K_{eq}A} = \dfrac{l}{KA} + \dfrac{l}{2KA}$
$\dfrac{2}{K_{eq}} = \dfrac{1}{K} + \dfrac{1}{2K} = \dfrac{3}{2K}$
$\Rightarrow K_{eq} = \dfrac{4}{3}K$