On which of the following four processes does the functioning of a bimetallic strip depend?
$(i)$ Radiation
$(ii)$ Energy conversion
$(iii)$ Melting
$(iv)$ Thermal expansion

$A$ lead ball moving with a velocity $V$ strikes a wall and stops. If $50\%$ of its energy is converted into heat,then what will be the increase in temperature? (Specific heat of lead is $S$)

$A$ bullet of mass $5\, g$,travelling with a speed of $210\, m/s$,strikes a fixed wooden target. One half of its kinetic energy is converted into heat in the bullet while the other half is converted into heat in the wood. The rise of temperature of the bullet if the specific heat of its material is $0.030\, cal/(g \cdot ^{\circ}C)$ $(1\, cal = 4.2 \times 10^{7}\, ergs)$ is close to $.......^{\circ}C$.

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

The pressure and volume of saturated water vapour are $P$ and $V$ respectively. It is compressed isothermally such that the volume becomes $V/2$. The final pressure will be

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