A metal bal of mass $0.1\, kg$ is heated upto $500\,{}^oC$ and dropped into a vessel of heat capacity $800\, JK^{-1}$ and containing $0.5\, kg$ water. The initial temperature of water and vessel is $30\,{}^oC$. …….. $\%$ is the approximate percentage increment in the temperature of the water. [Specific heat Capacities of water and metal are, respectively $4200\, Jkg^{-1}K^{-1}$ and $400\, Jkg^{-1}K^{-1}$]

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 :

$50\, g$ ice at $0\,^oC$ is dropped into a calorimeter containing $100\, g$ water at $30\,^oC$. If thermal capacity of calorimeter is zero then amount of ice left in the mixture at equilibrium is …….. $gm$

The water equivalent of $20 \,g$ of aluminium (specific heat $0.2 \,cal ^{-1}{ }^{\circ} C ^{-1}$ ), is ……… $g$

The temperature of equal masses of three different liquids ${x}, {y}$ and ${z}$ are $10^{\circ} {C}, 20^{\circ} {C}$ and $30^{\circ} {C}$ respectively. The temperature of mixture when ${x}$ is mixed with ${y}$ is $16^{\circ} {C}$ and that when ${y}$ is mixed with $z$ is $26^{\circ} {C}$. The temperature of mixture when $x$ and $z$ are mixed will be …… $^{\circ} {C}$