<P> Internal energy is the sum of all microscopic forms of energy of a system . It is the energy needed to create the system . It is related to the potential energy , e.g. , molecular structure , crystal structure , and other geometric aspects , as well as the motion of the particles , in form of kinetic energy . Thermodynamics is chiefly concerned with changes in internal energy and not its absolute value , which is impossible to determine with thermodynamics alone . </P>
<P> Internal energy is the sum of all microscopic forms of energy of a system . It is the energy needed to create the system . It is related to the potential energy , e.g. , molecular structure , crystal structure , and other geometric aspects , as well as the motion of the particles , in form of kinetic energy . Thermodynamics is chiefly concerned with changes in internal energy and not its absolute value , which is impossible to determine with thermodynamics alone . </P>
the sum of the kinetic and potential energies of all the particles in a system is called its
the sum of the kinetic and potential energies of all the particles in a system is called its
Internal energy
Internal energy