The coefficient of thermal conductivity depends upon
Temperature difference of two surfaces
Area of the plate
Thickness of the plate
Material of the plate
The dimensional formula for thermal resistance is
Which of the following statements is/are $CORRECT$ Correct option are
$(i)$ a body with large reflectivity is a poor emitter
$(ii)$ a brass tumbler feels much colder than a wooden tray on a chilly day
$(iii)$ the earth without its atmosphere would be inhospitably cold
$(iv)$ heating systems based on circulation of steam are more efficient in warming a building than those based on circulation of hot water
Two rectangular blocks $A$ and $B$ of different metals have same length and same area of cross-section. They are kept in such a way that their cross-sectional area touch each other. The temperature at one end of $A$ is $100°C$ and that of $B$ at the other end is $0°C$ . If the ratio of their thermal conductivity is $1 : 3$ , then under steady state, the temperature of the junction in contact will be ........ $^oC$
The two opposite faces of a cubical piece of iron (thermal conductivity $= 0.2\, CGS$ units) are at ${100^o}C$ and ${0^o}C$ in ice. If the area of a surface is $4c{m^2}$, then the mass of ice melted in $10$ minutes will be ...... $gm$
If the ratio of coefficient of thermal conductivity of silver and copper is $10 : 9$ , then the ratio of the lengths upto which wax will melt in Ingen Hausz experiment will be