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If 1 eV is equivalent to a certain value in joules, what is that value?

  1. 1.2 * 10^-19 J

  2. 1.4 * 10^-19 J

  3. 1.6 * 10^-19 J

  4. 1.8 * 10^-19 J

The correct answer is: 1.6 * 10^-19 J

The concept of electronvolts (eV) is fundamental in atomic and particle physics, where it quantifies energy. One electronvolt is defined as the energy gained by an electron when it is accelerated through an electric potential difference of one volt. To convert electronvolts to joules, one can use the relationship: 1 eV = 1.6 x 10^-19 J This value comes from the multiplication of the charge of an electron (approximately 1.602 x 10^-19 coulombs) by the potential difference of one volt. Therefore, when looking for the equivalent of 1 eV in joules, the conversion leads directly to 1.6 x 10^-19 J, making it the correct answer in this context. The other options do not correspond to the recognized conversion factor for electronvolts to joules and do not align with the established scientific definition. This highlights why understanding the conversion from eV to joules, specifically identifying the correct numerical representation, is essential in physics.