Conduction Questions

Which of the following circular rods, (given radius r and length l) each made of the same material and whose ends are maintained at the same temperature will conduct most heat ?

The two ends of a rod of length $L$ and a uniform cross-sectional area $A$ are kept at two temperatures $T_1$ and $T_2$ ($T_1>T_2$). The rate of heat transfer, $\frac{dQ}{dt}$, through the rod in a steady state is given by:

A cylindrical metallic rod in thermal contact with two reservoirs of heat at its two ends conducts an amount of heat $Q$ in time $t$. The metallic rod is melted and the material is formed into a rod of half the radius of the original rod. What is the amount of heat conducted by the new rod, when placed in thermal contact with the two reservoirs in time $t$?

A slab of area $0.36{\text{m}}^2$ and thickness $0.1\text{m}$ has ice on upper surface ($0^{\circ }\text{C}$) and steam on lower surface ($100^{\circ }\text{C}$). In one hour $4.8\text{kg}$ of ice melts. Thermal conductivity of slab is: ($L_f=3.36\times 10^5{\text{J kg}}^{-1}$)