$A$ bullet of mass $m$ moving with a uniform velocity $v$ stops suddenly after hitting a target. If the whole mass melts,given the specific heat $S$,initial temperature $25^{\circ}C$,melting point $475^{\circ}C$,and latent heat $L$,then $v$ is given by:

$Assertion :$ In the pressure-temperature $(P-T)$ phase diagram of water,the slope of the melting curve is found to be negative.
$Reason :$ Ice contracts on melting to water.

The variation of density of water with temperature is represented by the

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 $= 1 \, cal/g^{\circ} C$)

How many $J$ of heat energy is required to convert $1\,g$ of ice at $-10^{\circ}C$ into steam at $100^{\circ}C$?

$A$ $20 \,g$ bullet whose specific heat is $5000 \,J/(kg \cdot ^{\circ}C)$ and moving at $2000 \,m/s$ plunges into a $1.0 \,kg$ block of wax whose specific heat is $3000 \,J/(kg \cdot ^{\circ}C)$. Both the bullet and the wax are at $25^{\circ}C$. Assuming that $(i)$ the bullet comes to rest in the wax and $(ii)$ all its kinetic energy is converted into heat,the final temperature of the wax (in $^{\circ}C$) is close to: