The figure given below shows the cooling curve of a pure wax material after heating. It cools from $A$ to $B$ and solidifies along $BD$. If $L$ and $C$ are the respective values of latent heat and the specific heat of the liquid wax,the ratio $L/C$ is

$A$ metallic ball and a highly stretched spring are made of the same material and have the same mass. They are heated so that they melt. The latent heat required:

An ice cube at temperature $-20^oC$ is kept in a room at temperature $20^oC$. The variation of temperature of the body with time is given by

The graph shown in the figure represents the change in the temperature of $5 \, kg$ of a substance as it absorbs heat at a constant rate of $42 \, kJ \, min^{-1}$. The latent heat of vaporization of the substance is ......... $kJ \, kg^{-1}$.

$Assertion :$ Melting of a solid causes no change in internal energy.
$Reason :$ Latent heat is the heat required to melt a unit mass of a solid.

An experiment takes $10\, minutes$ to raise the temperature of water in a container from $0\,^oC$ to $100\,^oC$ and another $55\, minutes$ to convert it totally into steam by a heater supplying heat at a uniform rate. Neglecting the specific heat of the container and taking the specific heat of water to be $1\, cal/g\,^oC$,the heat of vaporization according to this experiment will be ........ $cal/g$.