Steam at $100^o C$ is added slowly to $1400 \,\,gm$ of water at $16^o C$ until the temperature of water is raised to $80^o C$. The mass of steam required to do this is ($L_V =$ $540\,\,cal/gm$) ........... $gm$
$160$
$125 $
$250$
$320$
$50\, gm$ of ice at $0°C$ is mixed with $50\, gm$ of water at $80°C,$ final temperature of mixture will be........ $^oC$
Pure water super cooled to $-15^o C$ is contained in a thermally insulated flask. Small amount of ice is thrown into the flask. The fraction of water frozen into ice is :
$100\,g$ of water is supercooled to $-\,10\,^oC$. At this point, due to some disturbance mechanised or otherwise some of it suddenly freezes to ice. What will be the temperature of the resultant mixture and how much mass would freeze ? $[S_W = 1\,cal\,g^{-1}\,^oC^{-1}$ and ${L^W}_{{\text{fussion}}}$ $= 80\,cal\,g^{-1}]$
A geyser heats water flowing at a rate of $2.0 kg$ per minute from $30^{\circ} C$ to $70^{\circ} C$. If geyser operates on a gas burner, the rate of combustion of fuel will be $\dots \; g \min ^{-1}$
[Heat of combustion $=8 \times 10^{3} Jg ^{-1}$ Specific heat of water $=4.2 Jg ^{-1} \; { }^{\circ} C ^{-1}$ ]
One kilogram of ice at $0°C$ is mixed with one kilogram of water at $80°C.$ The final temperature of the mixture is........ $^oC$
$($Take : specific heat of water$ = 4200\,J\,k{g^{ - 1}}\,{K^{ - 1}}$, latent heat of ice $ = 336\,kJ\,k{g^{ - 1}})$