$500 \ g$ of water is heated from $30^{\circ}C$ to $90^{\circ}C$. What is the change in its internal energy? (Specific heat of water is $4184 \ J \ kg^{-1} \ K^{-1}$)

Define specific heat capacity and write its $SI$ unit.

Water is used to cool radiators of engines,because

$A$ 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,

$50 \text{ g}$ 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 $^{\circ} \text{C}$)

What is the molar specific heat capacity of a substance? Write its unit.