# GATE ME 2013 | Question: 9

Consider one-dimensional steady state heat conduction, without heat generation, in a plane wall; with boundary conditions as shown in the figure below. The conductivity of the wall is given by $k$ = $k_0$ + $bT$  ; where $k_0$ and $b$ are positive constants, and $T$ is temperature.

As $x$ increases, the temperature gradient ( $dT$/ $dx$ ) will

1. remain constant
2. be zero
3. increase
4. decrease

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