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GATE 2021 MT – Question 43

Transport Phenomena and Rate Processes · Heat transfer · 2 marks · Multiple choice

The shown steady one-dimensional temperature distribution is across adjacent refractory blocks of unit cross-sectional area and conductivities $k_1,k_2$. Temperature $T_1$ and interface thermal contact resistance, respectively, are ______.

Diagram for GATE 2021 MT question 43
  1. 200 K, 0.5 K/W
  2. 400 K, 1.0 K/W
  3. 200 K, 0.25 K/W
  4. 500 K, 0.5 K/W

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Show answer and explanation

Correct answer: (A) 200 K, 0.5 K/W

Explanation

Heat rate through the first unit-area block is 2(1000−800)/1=400 W. The interface jump is 800−600=200 K, so contact resistance is 200/400=0.5 K/W. The second block drops 400×1/1=400 K to **T1=200 K, A**.