# Electron Volt: Definition and Concept

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An electron volt is the measure of dynamic energy picked up or lost by a solitary electron quickening from rest through an electric potential distinction of one volt in vacuum. Henceforth, it has an estimation of one volt, 1 J/C, increased by the electron’s rudimentary charge e, 1.6021766208(98)×10−19 C. Along these lines, one electron volt is equivalent to 1.6021766208(98)×10−19 J.

The electron volt, instead of volt, isn’t a SI unit. Its inference is observational, which implies its incentive in SI units must be acquired by examination and is in this way not known precisely, in contrast to the liter, the light-year and such other non-SI units. Electon volt (eV) is a unit of energy though volt (V) is the determined SI unit of electric potential. The SI unit for energy is joule (J). 1 eV is equivalent to 1.6021766208(98)×10−19 J.

# What is Electron Volt? Definition and Concept

Electron volts, like joules, are a unit of energy. This may sound confusing- why two? But think of it this way; length has two possible units- metric (metres) and imperial (inches). We can use either units to measure length and can switch between the two. The same is true of joules and electron volts.

## Concept of Electron Volt

The concept of electron volt is very simple. We know the unit of power is watt. W = VI, where V is the voltage and I is the current. Presently as I is current, it is only rate of charge exchange. Therefore, quick impression of intensity would be

Where, q(t) is the amount of charge transferred in time t.

Now energy is expressed as

Where, q is the charge in Coulomb crosses a voltage V volts.

## Electron Volt to Joules

From the expression of energy we can write the energy required or work to be done for crossing an electric field of total voltage V by a charge Q coulomb is QV coulomb – volt or joules.

Now we know the charge of an electron is – 1.6 × 10-19 coulomb and consider it has crossed an electric field of total voltage 1 V. Then the total work to be done is charge of electron × 1 V.

This amount of energy is considered as a micro unit of energy called electron-volt.

## Electron Volt Momentum

In high-vitality material science, the electron volt is regularly utilized as a unit of energy. A potential contrast of 1 volt makes an electron gain a measure of vitality (i.e., 1 eV). This offers ascend to utilization of eV (and keV, MeV, GeV or TeV) as units of force, for the vitality provided results in speeding up of the molecule.

The components of force units are LMT−1. The elements of vitality units are L2MT−2. At that point, separating the units of vitality, (for example, eV) by a basic consistent that has units of speed (LT−1), encourages the required transformation of utilizing vitality units to depict energy. In the field of high-vitality molecule material science, the crucial speed unit is the speed of light in vacuum c.

By partitioning vitality in eV by the speed of light, one can portray the force of an electron in units of eV/c.

The essential speed steady c is regularly dropped from the units of energy by method for characterizing units of length with the end goal that the estimation of c is solidarity. For instance, if the force p of an electron is said to be 1 GeV, at that point the change to MKS can be accomplished by: