How many joules are in 1 electron volt?

One electron volt (eV) is defined as the amount of energy gained by an electron when it is accelerated through an electric potential difference of one volt. The relationship between electron volts and joules is based on the fundamental charge of the electron, which is approximately 1.6 x 10^-19 coulombs. Since energy (in joules) is calculated as the product of charge (in coulombs) and electric potential (in volts), for an electron accelerated through one volt, the energy is:

Energy (J) = Charge (C) x Voltage (V) = (1.6 x 10^-19 C) x (1 V) = 1.6 x 10^-19 J.

This conversion is essential in many fields of physics, including quantum mechanics and radiation therapy, as it relates the energy levels of particles and the energy of photons and other forms of radiation. Hence, the value of 1 electron volt is accurately represented as 1.6 x 10^-19 joules.