Question

Two ends of a rod of non-uniform area of cross-section are maintained at temperature $T_1$ and $T_2(T_1>T_2)$ as shown in the figure. If $I$ is the heat current through the cross - section of the conductor at distance $x$ from its left face then the variation of $I$ with time $t$ is best represented by

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

At the steady state, the rate of heat transfer through any cross - section is constant with respect to time.
Therefore, the graph will be a straight line parallel to the time axis.