High Quality Content by WIKIPEDIA articles! Specific energy is defined as the energy per unit mass. Common metric units are J/kg or, in basic SI units: m2/s2. It is an intensive property. Contrast this with energy, which is an extensive property. There are two main types of specific energy: field strength and strength of movement. Others are the gray and sievert, measures for the absorption of radiation.Thermodynamic properties related to specific energy include specific internal energy, specific enthalpy, specific Gibbs free energy, and specific Helmholtz free energy, all of which use units of energy per mass such as J/kg. These intensive properties are each symbolized by using the lower case letter of the symbol for the corresponding extensive property, which is symbolized by a capital letter. For example, the extensive thermodynamic property enthalpy is symbolized by H; specific enthalpy is symbolized by h.