Two rods (one semi-circular and one straight) are made of the same material and have the same cross-sectional area. They are joined as shown in the figure. Points $A$ and $B$ are maintained at different temperatures. The ratio of the heat current flowing through the semi-circular rod to that flowing through the straight rod in a given time is:

In Searle's method for finding the thermal conductivity of metals,the temperature gradient along the bar:

Heat current is maximum in which of the following (rods are of identical dimension)?

The walls of a closed cubical box of edge $60 \text{ cm}$ are made of material of thickness $1 \text{ mm}$ and thermal conductivity $4 \times 10^{-4} \text{ cal s}^{-1} \text{ cm}^{-1} {}^{\circ}\text{C}^{-1}$. The interior of the box is maintained $1000^{\circ}\text{C}$ above the outside temperature by a heater placed inside the box and connected across a $400 \text{ V}$ $DC$ supply. The resistance of the heater is: (in $\Omega$)

Consider two rods $1$ and $2$ of same length $L$. They have different specific heats $(C_1, C_2)$, thermal conductivities $(K_1, K_2)$ and area of cross-section $(A_1, A_2)$ respectively. Both the rods have temperatures $(T_1, T_2)$ at their ends. If their rate of loss of heat due to conduction is equal, then

Which of the following cylindrical rods will conduct the most heat when their ends are maintained at the same steady temperature difference?