$A$ copper block of mass $2.5\; kg$ is heated in a furnace to a temperature of $500\; ^{\circ}C$ and then placed on a large ice block. What is the maximum amount of ice (in $kg$) that can melt? (Specific heat of copper $= 0.39\; J\; g^{-1}\; K^{-1}$; heat of fusion of water $= 335\; J\; g^{-1}$)

Two different liquids of same mass are kept in two identical vessels,which are placed in a freezer that extracts heat from them at the same rate,causing each liquid to transform into a solid. The schematic figure below shows the temperature $T$ versus time $t$ plot for the two materials. We denote the specific heat of materials in the liquid (solid) states to be $C_{L1}$ $(C_{S1})$ and $C_{L2}$ $(C_{S2})$,respectively. Choose the correct option given below.

Out of the following,in which vessel will the temperature of the solution be higher after the salt is completely dissolved?

If the ratio of densities of two substances is $5:6$ and the ratio of their specific heat capacities is $3:5$,then the ratio of heat energies required per unit volume so that the two substances can have the same temperature rise is

$A$ waterfall is $84 \ m$ high. If half of the potential energy of the falling water gets converted to heat,the rise in temperature of the water will be: (in $^\circ C$)

$A$ hunter fired a metallic bullet of mass $m \ kg$ from a gun towards an obstacle and it just melts when it is stopped by the obstacle. The initial temperature of the bullet is $300 \ K$. If $\frac{1}{4}$ th of the heat is absorbed by the obstacle,then the minimum velocity of the bullet is (Melting point of bullet $= 600 \ K$,Specific heat of bullet $= 0.03 \ cal \ g^{-1} {}^{\circ} C^{-1}$,Latent heat of fusion of bullet $= 6 \ cal \ g^{-1}$) (in $ms^{-1}$)