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
$3 a$
$\frac{{15\,a}}{4}$
$\frac{{2\,a}}{3}$
$\frac{{12\,a}}{5}$
A calorimeter contains $0.2\, kg$ of water at $30\,^oC$, $0.1\,kg$ of water at $60\,^oC$ is added to it, the mixture is well stirred and the resulting temperature is found to be $35\,^oC$. The thermal capacity of calorimeter is .......... $J/K$
A heater supplying constant power $P$ watts is switched $ON$ at time $t=0 \,min$ to raise the temperature of a liquid kept in a calorimeter of negligible heat capacity. A student records the temperature of the liquid $T(t)$ at equal time intervals. A graph is plotted with $T(t)$ on the $Y$-axis versus $t$ on the $X$-axis. Assume that there is no heat loss to the surroundings during heating. Then,
Equal masses of three liquids $A, B$ and $C$ have temperatures $10\,^oC$, $25\,^oC$ and $40\,^oC$ respectively. If $A$ and $B$ are mixed, the mixture has a temperature of $15\,^oC$. If $B$ and $C$ are mixed then mixture has temperature of $30\,^oC$. If $A$ and $C$ are mixed, the mixture will have a temperature of ........ $^oC$
$80\, gm$ of water at $30°C$ are poured on a large block of ice at $0°C.$ The mass of ice that melts is ........ $gm$
Heat is being supplied at a constant rate to the sphere of ice which is melting at the rate of $0.1 \,gm / s$. It melts completely in $100 \,s$. The rate of rise of temperature thereafter will be ............ $^{\circ} C / s$