Elektronivolttien

Elektronivoltti, often abbreviated as eV, is a unit of energy commonly used in atomic, nuclear, and particle physics. It is defined as the amount of kinetic energy gained by a single electron when it is accelerated through an electric potential difference of one volt. The symbol for electronvolt is eV.

The value of one electronvolt in joules is approximately 1.602 x 10^-19 joules. This conversion factor is derived from the elementary charge of an electron (e) and the definition of a volt. Due to its small magnitude, electronvolts are much more convenient than joules for describing the energies involved in interactions at the atomic and subatomic scales.

Electronvolts are particularly useful for expressing the energy of photons, ionization energies of atoms, and the masses of elementary particles. For instance, the energy of visible light photons is typically measured in a few electronvolts, while the binding energy of electrons in atoms can range from a few eV to hundreds of eV. In nuclear reactions and particle physics, energies can reach millions or even billions of electronvolts (MeV and GeV, respectively). The concept of electronvolts simplifies calculations and comparisons within these fields.