Why is water used as a coolant?

The amount of heat required to raise the temperature of a body by $1^oC$ is called its

On which factor does the required amount of heat depend to increase the temperature of a substance?

The figure below shows the variation of specific heat capacity $(C)$ of a solid as a function of temperature $(T)$. The temperature is increased continuously from $0$ to $500 \ K$ at a constant rate. Ignoring any volume change,which of the following statement$(s)$ is (are) correct to a reasonable approximation?
$(A)$ The rate at which heat is absorbed in the range $0-100 \ K$ varies linearly with temperature $T$.
$(B)$ Heat absorbed in increasing the temperature from $0-100 \ K$ is less than the heat required for increasing the temperature from $400-500 \ K$.
$(C)$ There is no change in the rate of heat absorption in the range $400-500 \ K$.
$(D)$ The rate of heat absorption increases in the range $200-300 \ K$.

Write the value of the specific heat capacity of water with its unit.

Two spheres made of the same substance have diameters in the ratio $1:2$. Their thermal capacities are in the ratio of: