Four rods of same material with different radii $r$ and length $l$ are used to connect two reservoirs of heat at different temperatures. Which one will conduct most heat ?

The coefficient of apparent expansion of mercury in a glass vessel is $153\times 10^{-6}/\,^oC$ and in a steel vessel is $144\times 10^{-6}/\,^oC.$ If $\alpha $ for steel is $12 \times 10^{-6}/\,^oC,$ then $\alpha $ that of glass is

A steel tape measures the length of a copper rod as $90\, cm$ when both are at $10\,^oC$. ........ $cm$ would the tape read for the length of rod when both are at $30\,^oC$ ? $[\alpha _{st} = 1.2\times10^{-5}/^oC$ and $\alpha _{cu} = 1.7\times10^{-5}/^oC]$

A vertical glass capillary tube open at both ends contains some water. Which of the following shapes may be taken by the water in the tube?

A small quantity, mass $m$ , of water at a temperature $\theta $ (in $^oC$ ) is poured on to a large mass $M$ of ice which is at its melting point. If $c$ is the specific heat of water and $L$ the latent heat of fusion of ice, then the mass of ice melted is given by

$200\, g$ of a solid ball at $20\,^oC$ is dropped in an equal amount of water at $80\,^oC$. The resulting temperature is $60\,^oC$. This means that specific heat of solid is