$A$ small electric heater is used to heat $200 \,g$ of water. The time required to bring all this water from $40^{\circ} C$ to $100^{\circ} C$ is $200 \,s$. If the specific heat of the water is $4200 \,J \,kg^{-1} \,K^{-1}$, then the power supplied by the heater is: (in $\,W$)

The quantities of heat required to raise the temperatures of two copper spheres of radii $r_{1}$ and $r_{2}$ $(r_{1} = 1.5 r_{2})$ through $1 \ K$ are in the ratio of:

$50 \text{ g}$ of copper is heated to increase its temperature by $10^{\circ} \text{C}$. If the same quantity of heat is given to $10 \text{ g}$ of water,the rise in temperature is (specific heat of $\text{Cu} = 420 \text{ J kg}^{-1} {}^{\circ} \text{C}^{-1}$ and specific heat of water is $4200 \text{ J kg}^{-1} {}^{\circ} \text{C}^{-1}$) (in $^{\circ} \text{C}$)

$A$ heater supplying constant power $P$ watts is switched $ON$ at time $t=0$ 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,

What is the total energy for one mole of a solid substance?

The temperature of $5$ moles of a gas which was held at constant volume was changed from $100^{\circ}C$ to $120^{\circ}C$. The change in internal energy was found to be $80$ Joules. The total heat capacity of the gas at constant volume will be equal to ...... $J/K$.