An earthen pitcher used in summer cools water in it essentially by evaporation of water from its porous surface. If a pitcher carries $4 \,kg$ of water and the rate of evaporation is $20 \,g$ per hour,the temperature of water in it decreases by $\Delta T$ in two hours. The value of $\Delta T$ is close to ........... $^{\circ} C$ (ratio of latent heat of evaporation to specific heat of water is $540^{\circ} C$).

$A$ stationary object at $4^{\circ} C$ and weighing $3.5 \ kg$ falls from a height of $2000 \ m$ on a snow mountain at $0^{\circ} C$. If the temperature of the object just before hitting the snow is $0^{\circ} C$ and the object comes to rest immediately,then the quantity of ice that melts is (Acceleration due to gravity $= 10 \ m/s^2$,Latent heat of ice $= 3.5 \times 10^5 \ J/kg$)

Thermal expansion due to an increase in temperature...

Match the following List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. When ice melts into water	$I$. Volume increases
$B$. When water changes into steam	$II$. Volume decreases
$C$. Melting point of ice	$III$. Increases with increase of pressure
$D$. Boiling point of water	$IV$. Decreases with increase in pressure

$A$ 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 $ms^{-1}$)

$A$ closed bottle containing water at $30^{\circ} C$ is opened on the surface of the moon. Then,