You would expect that the fast moving atoms in one gas would bump into the slower moving ones in the other gas. Again, the amount of internal energy that flows is called heat . Something is 'hot' when energy can readily flow from it to something else, and 'cool' when it can readily gain energy from other objects. Physical systems tend to approach thermodynamic equilibrium or tend toward a situation of equal energies. We quantify this characteristic as temperature .
Temperature is a measure of the average internal energy per atom or molecule.
Another example of a system tending toward thermodynamic equilibrium is that of ice cubes melting in a glass of your favorite beverage. When we heat an object, we increase its internal energy, and hence its temperature. The specific heat of a material is the number of joules required to raise the temperature of one gram of the material one degree Celsius. In this lab you will measure the specific heat capacity of several substances. Synopsis of Exercise Find the specific heat of several objects.