Electronvolt

An electronvolt is a unit of energy commonly used to measure the energy carried by individual particles and electromagnetic radiation.

  • Electronvolts can be used to measure the energy of elementary particles, including photons, which are the smallest units of electromagnetic radiation (quanta of the electromagnetic field.
  • One electronvolt is the energy gained by a single electron when it is accelerated across a potential difference of 1 volt.
  • If there is a voltage difference of 1 volt between two points in an electrical circuit (such as across a capacitor), then the energy gained by a photon when it accelerates between those points is equivalent to 1 electronvolt.
  • The electronvolt is not part of the SI unit system for measurements.
  • The joule, which is an SI unit of measurement, is not practical for measurements at the particle physics because it is a relatively large unit, more suited to measurements in everyday life such as the energy consumed by electrical appliances, the energy required to heat substances etc.
  • 1,000,000,000,000,000,000 electronvolts is equivalent to approximately 0.1602176565 joules.
  • The electronvolt is often used in conjunction with metric prefixes to represent energy values at different magnitudes.

An electronvolt is a unit of energy commonly used to measure the energy carried by electromagnetic radiation.

  • Electronvolts can be used for measurements at the scale of elementary particles as small as single photons, the quantum of the electromagnetic field.
  • One electronvolt is the amount of energy that a single electron has when it is accelerated by a potential difference of 1 volt.
  • If there is a difference in voltage of 1 volt between two points in an electrical circuit (within a capacitor for example) then the force required (and the energy gained) by a photon accelerating from one point to the other is 1 electronvolt.