Question

One million electron volt (\[1\,{\text{MeV}}\]) is equal to
A. \[{10^5}\,{\text{eV}}\]
B. \[{10^6}\,{\text{eV}}\]
C. \[{10^4}\,{\text{eV}}\]
D. \[{10^7}\,{\text{eV}}\]

Answer 1

Hint:Recall the different conversion factors related with the conversion like kilo, mega, micro, million, billion, etc. Using the basics of these conversion factors, check what will be the value of one million electron volt in electron volt from the given options.

Complete answer:
The value of one million is \[{10^6}\].Therefore, one million electronvolt must be equal to \[{10^6}\,{\text{eV}}\].

\[1\,{\text{MeV}} = {10^6}\,{\text{eV}}\]

Additional information:
There are various units of energy joule, erg, electron volt, etc. The units joule or erg are used for the energy of any physical object.The unit electron volt is used for the energy of the atomic or subatomic charged particles in nuclear and atomic physics. One electronvolt is the energy (which may be lost or gained) of the electron when there is an electric potential difference of one volt in vacuum. The unit electron volt is denoted as eV.
The value of one electron volt in SI system of units which is joule is \[1.602 \times {\text{1}}{{\text{0}}^{ - 19}}\,{\text{J}}\].
\[1\,{\text{eV}} = 1.602 \times {\text{1}}{{\text{0}}^{ - 19}}\,{\text{J}}\]
In particle physics, the unit electron volt is also used for mass of the particles because the physical quantities mass and energy are interchangeable.
There are various conversion factors of energy in electron volt such as one kilo-electron volt is equal to one thousand electron volt, one mega-electron volt is equal to one million electron volt, one giga-electron volt is equal to one thousand electron volt, etc.

Note:The students should perfectly keep in mind the conversion factors. If these conversion factors are not used correctly then the final answer for the asked conversion will be incorrect. Therefore, the students should be careful while converting the unit from one system to another system.