The thermal conductivities of copper,mercury,and glass are $K_c$,$K_m$,and $K_g$ respectively,such that $K_c > K_m > K_g$. If the same amount of heat flows per unit time through a unit cross-sectional area for each,what is the relationship between their temperature gradients $(X_c, X_m, X_g)$?

The area of a glass window is $10 \ m^2$ and its thickness is $2 \ mm$. The outside and inside temperatures are $40^{\circ}C$ and $20^{\circ}C$ respectively. The thermal conductivity in $MKS$ units is $0.2$. The heat conducted per second into the room is ......

The thermal conductivity of a rod is $2$. What is its thermal resistivity?

Two ends of rods of length $L$ and radius $r$ of the same material are kept at the same temperature difference. Which of the following rods conducts the most heat?

Define thermal conductivity. Also,provide its $SI$ unit and dimensional formula.

Two rectangular blocks $A$ and $B$ of different metals have the same length and the same area of cross-section. They are kept in such a way that their cross-sectional areas touch each other. The temperature at one end of $A$ is $100^{\circ}C$ and that of $B$ at the other end is $0^{\circ}C$. If the ratio of their thermal conductivities is $1 : 3$,then under steady state,the temperature of the junction in contact will be ........ $^{\circ}C$.