Two materials having coefficients of thermal conductivity ‘ $3 K$ ‘ and ‘ $K$ ‘ and thickness ‘ $d$ ‘ and ‘ $3 d$ ‘, respectively, are joined to form a slab as shown in the figure. The temperatures of the outer surfaces are ‘ $\theta_{2}$ ‘ and ‘ $\theta_{1}$ ‘ respectively, $\left(\theta_{2}>\theta_{1}\right)$. The temperature at the interface is:

Question:

Two materials having coefficients of thermal conductivity ‘ $3 K$ ‘ and ‘ $K$ ‘ and thickness ‘ $d$ ‘ and ‘ $3 d$ ‘, respectively, are joined to form a slab as shown in the figure. The temperatures of the outer surfaces are ‘ $\theta_{2}$ ‘ and ‘ $\theta_{1}$ ‘ respectively, $\left(\theta_{2}>\theta_{1}\right)$. The temperature at the interface is:

  1. $\frac{\theta_{1}}{10}+\frac{9 \theta_{2}}{10}$

  2. $\frac{\theta_{2}+\theta_{1}}{2}$

  3. $\frac{\theta_{1}}{6}+\frac{5 \theta_{2}}{6}$

  4. $\frac{\theta_{1}}{3}+\frac{2 \theta_{2}}{3}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Termal Properties of Matter chapter.

JEE Main Previous Year 9 April 2019 II


Correct Option: 1

Solution:

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