- Mass defect: The mass defect is the difference between the mass of a fully assembled nucleus and the sum of the individual masses of its constituent protons and neutrons. It represents the mass converted into energy during the formation of the nucleus.
\[
\text{Mass Defect} = \left( \text{sum of masses of individual nucleons} \right) - \text{mass of the nucleus}.
\]
- Binding energy: The binding energy of a nucleus is the energy required to break it apart into its constituent nucleons (protons and neutrons). It is equal to the energy equivalent of the mass defect.
\[
E_b = \Delta m \cdot c^2,
\]
where \( \Delta m \) is the mass defect, and \( c \) is the speed of light.