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

$A$ 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 $^\circ C$)

$A$ glass flask of volume $200 \, cm^3$ is just filled with mercury at $20^{\circ} C$. The amount of mercury that will overflow when the temperature of the system is raised to $100^{\circ} C$ is ........ $cm^3$ $(\gamma_{\text{glass}} = 1.2 \times 10^{-5} /^{\circ}C, \gamma_{\text{mercury}} = 1.8 \times 10^{-4} /^{\circ}C)$

Water falls from a height of $210 \, m$. Assuming the whole of the energy due to the fall is converted into heat,the rise in temperature of water would be .......... $^\circ C$ $(J = 4.3 \, J/cal)$.

The point on the pressure-temperature phase diagram where all three phases (solid,liquid,and gas) co-exist is called:

The height of Victoria Falls is $63 \ m$. What is the difference in temperature of water at the top and at the bottom of the fall? (In $^{\circ}C$)
[Given $1 \ cal = 4.2 \ J$ and specific heat of water $= 1 \ cal \ g^{-1} \ ^{\circ}C^{-1}$]