An aluminium piece of mass $50 \,g$ initially at $300^{\circ} C$ is dipped quickly and taken out of $1 \,kg$ of water, initially at $30^{\circ} C$. If the temperature of the aluminium piece immediately after being taken out of the water is found to be $160^{\circ} C$, the temperature of the water ............ $^{\circ} C$ Then, specific heat capacities of aluminium and water are $900 \,Jkg ^{-1} K ^{-1}$ and $4200 \,Jkg ^{-1} K ^{-1}$, respectively.

In an industrial process $10\, kg$ of water per hour is to be heated from $20^o C$ to $80^o C$ . To do this steam at $200^o C$ is passed from a boiler into a copper coil immersed in water. The steam condenses in the coil and is returned to the boiler as water at $90^o C$. How many kg of steam is required per hour. (Specific heat of steam $= 0.5\, cal/g^o C$, Latent heat of vaporisation $= 540 cal/g)$

An experiment takes $10\, minutes$ to raise the temperature of water in a container from $0\,^oC$ to $100\,^oC$ and another $55\, minutes$ to convert it totally into steam by a heater supplying heat at a uniform rate . Neglecting the specific heat of the container and taking specific heat of water to be $1\, cal / g\,^oC$, the heat of vapourization according to this experiment will come out to be ........ $cal/g$

An aluminium container of mass $100\,\, gm$ contains $200 \,\,gm$ of ice at $-20^o\,\, C$. Heat is added to the system at the rate of $100 \,\,cal/s$. The temperature of the system after $4$ minutes will be ....... $^oC$ (specific heat of ice $= 0.5$ and $L = 80 \,\,cal/gm$, specific heat of $Al= 0.2\,\, cal/gm/^o C$)

$50 \,gm$ ice at $0°C$ in insulator vessel, $50g$ water of $100°C$ is mixed in it, then final temperature of the mixture is (neglect the heat loss)

Find the quantity of heat required to convert $40\; gm$ of ice at $-20^{\circ} C$ into water at $20^{\circ} C$. Given $L _{\text {ice }}$ $=0.336 \times 10^6 J / kg$.

specific heat of ice $=2100 \;J / kg - K$ sp heat of water= $4200\; J / kg - K$