In dealing with energy balance equations, we often need to calculate energy change upon temperature change.
Heat capacity is the thermal energy required to change the temperature of a material, thus so the heat change upon temperature change can be calculated by integrating heat capacity over the range of temperature range. In the second week, we will apply the energy balance equations to real problems and calculate the energy difference between two states. In these kinds of calculation, heat capacities are particularly required. Here, we introduce the concept of heat capacity and their physical meaning in preparation for the second week.