MCQ
Two rectangular blocks, having indentical dimensions, can be arranged either in configuration $I$ or in configuration $II$ as shown in the figure, On of the blocks has thermal conductivity $k$ and the other $2 \ k$. The temperature difference between the ends along the $x$-axis is the same in both the configurations. It takes $9\ s$ to transport a certain amount of heat from the hot end to the cold end in the configuration $I$. The time to transport the same amount of heat in the configuration $II$ is :


- ✓$2.0 \ s$
- B$3.0 \ s$
- C$4.5 \ s$
- D$6.0 \ s$

