Question

Define 'Mass defect' and 'Binding energy' of a nucleus. Describe 'Fission process' on the basis of binding energy per nucleon.

Hint:

The fission process is driven by the increase in binding energy per nucleon as large nuclei split into smaller ones, releasing energy.

Answer 1

- **Mass Defect:** The mass defect of a nucleus is the difference between the total mass of the individual nucleons (protons and neutrons) that make up the nucleus and the actual mass of the nucleus. Mathematically, it is: \[ \Delta m = \text{Mass of nucleons} - \text{Mass of nucleus} \] - **Binding Energy:** The binding energy of a nucleus is the energy required to separate the nucleus into its constituent protons and neutrons. It is related to the mass defect by Einstein’s equation \( E = \Delta m c^2 \).
- **Fission Process:** Nuclear fission is the process in which a heavy nucleus, such as uranium-235, splits into two or more smaller nuclei along with the release of a large amount of energy. This process occurs when a nucleus absorbs a neutron and becomes unstable. The binding energy per nucleon increases as the nucleus splits, which releases energy due to the higher binding energy of the fission products.