A drilling machine of $10\,KW$ power is used to drill a bore in a small aluminium block of mass $8\,kg.$ If $50\%$ of power is used up in heating the machine itself or lost to the surroundings then ........ $^oC$ is the rise in temperature of the block in $2.5\,minutes$
[specific heat of aluminium $= 0.91\,J/g\,\,^oc$ ]
$103$
$130$
$105$
$30$
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 ........ $cal/g$
A mass of material exists in its solid format its melting temperature $0\,^o C$. The following processes then occur to the material
Process $-1$:An amount of thermal energy $Q$ is added to the material and $\frac{2}{3}$ of the material melts.
Process $-2$:An identical additional amountof thermal energy $Q$ is added to the materlal is now a liquid at $4\,^o C$
........ $^oC$ is the ratio of the latent heat of fusion to the specific heat of the liquid for this material.
Calculate the heat required to convert $3\; kg$ of ice at $-12\,^{\circ} C$ kept in a calorimeter to steam at $100\,^{\circ} C$ at atmospheric pressure. Given specific heat capacity of $ice =2100\; J \,kg ^{-1} K ^{-1}$. specific heat capacity of water $=4186\; J kg ^{-1} K ^{-1}$, latent heat of fusion of ice $=3.35 \times 10^{5} \;J \,kg ^{-1}$ and latent heat of steam $=2.256 \times 10^{6}\; J \,kg ^{-1}$
$2\, kg$ of ice at $-20°C$ is mixed with $5\, kg$ of water at $20°C$ in an insulating vessel having a negligible heat capacity. Calculate the final mass of water remaining in the container. It is given that the specific heats of water and ice are $1\, kcal/kg\, per °C$ and $0.5\, kcal/kg/°C$ while the latent heat of fusion of ice is $80\, k\,cal/kg$ ........ $kg$
The specific heat of a metal at low temperatures varies according to $S = aT^3$ where a is a constant and $T$ is the absolute temperature. The heat energy needed to raise unit mass of the metal from $T = 1 K$ to $T = 2 K$ is