Heat The "molar heat capacity" is the heat capacity per unit amount (SI unit: mole) of a pure substance, and the "specific heat capacity", often called simply "specific heat", is the heat capacity per unit mass of a material. Heat capacity is a physical property of a substance, which means that it depends on the state and properties of the substance under consideration. The specific heats of monatomic gases, such as helium, are nearly constant with temperature. Diatomic gases such as hydrogen display some temperature dependence, and triatomic gases (e.g., carbon dioxide) still more. Before the development of the laws of
Intensity (physics) Intensity (physics) In physics, intensity is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy. In the SI system, it has units watts per square metre (W/m). It is used most frequently with waves (e.g. sound or light), in which case the "average" power transfer over one period of the wave is used. "Intensity" can be applied to other circumstances where energy is transferred. For example, one could calculate the intensity of the kinetic energy carried by drops of water from a garden sprinkler. The word