$A$ given mass $m$ of a hypothetical solid is supplied with heat continuously at a constant rate and the graph shown in the figure is plotted. If $L_f$ and $L_v$ are latent heats of fusion and vaporization,and $S_l$ and $S_s$ are specific heats of liquid and solid respectively,it can be concluded that:

Which form of heat was believed in before the modern time?

An aluminium container of mass $100 \, g$ contains $200 \, g$ of ice at $-20^{\circ} C$. Heat is added to the system at the rate of $100 \, cal/s$. The temperature of the system after $4$ minutes will be ....... $^{\circ} C$ (specific heat of ice $= 0.5 \, cal/g^{\circ} C$,latent heat of fusion $L = 80 \, cal/g$,specific heat of $Al = 0.2 \, cal/g^{\circ} C$,specific heat of water $= 1 \, cal/g^{\circ} C$)

$A$ closed bottle containing water at $30^{\circ}C$ is carried to the moon in a spaceship. If it is placed on the surface of the moon,what will happen to the water as soon as the lid is opened?

Heat required to convert $5\ kg$ of ice at $0\ ^oC$ into water at $100\ ^oC$ is:

The height of a waterfall is $50 \ m$. If $g = 9.8 \ m/s^2$, the difference between the temperature at the top and the bottom of the waterfall is: (in $^{\circ} C$)