$m$ g of water at $30^{\circ} C$ is mixed with $5$ g of ice at $-20^{\circ} C$. If the final equilibrium temperature of the mixture is $6^{\circ} C$,find the value of $m$. (Given: specific heat capacity of ice $= 0.5 \text{ cal g}^{-1} {}^{\circ} C^{-1}$,specific heat capacity of water $= 1 \text{ cal g}^{-1} {}^{\circ} C^{-1}$,and latent heat of fusion of ice $= 80 \text{ cal g}^{-1}$) (in $g$)

$A$ thermos flask contains $250 \ g$ of coffee at $90^{\circ} C$. To this $20 \ g$ of milk at $5^{\circ} C$ is added. After equilibrium is established, the temperature of the liquid is (Assume no heat loss to the thermos bottle. Take specific heat of coffee and milk as $1.00 \ cal/g^{\circ} C$) (in $^{\circ} C$)

$A$ small quantity,mass $m$,of water at a temperature $\theta$ (in $^oC$) is poured onto a large mass $M$ of ice which is at its melting point. If $c$ is the specific heat of water and $L$ is the latent heat of fusion of ice,then the mass of ice melted is given by

Ice at $-20\,^{\circ}C$ is added to $50\,g$ of water at $40\,^{\circ}C.$ When the temperature of the mixture reaches $0\,^{\circ}C,$ it is found that $20\,g$ of ice is still unmelted. The amount of ice added to the water was close to ........$g$ (Specific heat of ice $= 2.1\,J/g/^{\circ}C,$ Specific heat of water $= 4.2\,J/g/^{\circ}C,$ Heat of fusion of water at $0\,^{\circ}C = 334\,J/g).$

$A$ sphere of $0.047 \; kg$ aluminium is placed for a sufficient time in a vessel containing boiling water,so that the sphere is at $100 \; ^{\circ}C$. It is then immediately transferred to a $0.14 \; kg$ copper calorimeter containing $0.25 \; kg$ water at $20 \; ^{\circ}C$. The temperature of the water rises and attains a steady state at $23 \; ^{\circ}C$. Calculate the specific heat capacity of aluminium in $kJ \; kg^{-1} K^{-1}$.

$0.1 \, m^3$ of water at $80 \, ^oC$ is mixed with $0.3 \, m^3$ of water at $60 \, ^oC$. The final temperature of the mixture is ........ $^oC$.