The energy equivalent of one atomic mass unit is

Explanation

Atomic mass unit. The atomic mass unit (written as amu) is 1/12th the actual mass of carbon `""_(6)C^(12)`.
As we know, 1 gram atom of an element contains `6.023xx10^(23)` atom (Avogado.s number).
Thus `6.023xx10^(23)` atoms of carbon weigh
`=12g`
1 atom of carbon weigh
`=(12xx10^(-3))/(6.023xx10^(23))`kg
Hence `1 amu=1/12 xx (12xx10^(-3))/(6.023xx10^(23))kg`
`=1.66xx10^(-27)kg`.
Relation between amu and Me V (or Energy equivalence of 1 amu.)
From Einstein.s mass energy relation, we have `E=m_(0)c^(2)`
where E is the energy equivalent of rest mass `m_(0)` and c is the velocity of light. Thus,
`E=1.66xx10^(-27)xx(3xx10^(8))^(2)J`
`=(1.66xx9xx10^(-11))/(1.6xx10^(-19))` eV
`=931.5 xx 10^(6) eV=931.5 ` M eV `( :. 1 eV = 1.6xx10^(-19)J)`
`~=931` M eV.