Nuclear fission is a nuclear reaction in which a heavy atomic nucleus, such as uranium-235 or plutonium-239, splits into two (or more) smaller nuclei, called fission fragments, along with the release of a large amount of energy and several free neutrons.
The process typically begins when the nucleus absorbs a neutron, becoming unstable. This instability causes it to split into two lighter nuclei and release:
- Kinetic energy of the fission fragments (main source of energy),
- Electromagnetic radiation (gamma rays),
- Free neutrons, which can go on to trigger further fission events — forming a chain reaction.
This released energy is based on Einstein’s mass-energy equivalence (E=mc²), where a tiny amount of mass is converted into a tremendous amount of energy.
Applications of nuclear fission:
- Nuclear power plants, where controlled fission in reactors generates heat to produce electricity,
- Nuclear weapons, where uncontrolled fission leads to explosive energy release.
Fission offers a powerful energy source but also poses challenges like radioactive waste, nuclear proliferation, and potential reactor accidents. Nevertheless, it remains a major component of the global energy mix and scientific research into cleaner and safer nuclear technologies continues.