Nuclear fission and nuclear fusion – basic principles
How it works
Nuclear fission is the splitting of heavy atomic nuclei (e.g. uranium-235) into smaller nuclei, releasing energy and neutrons. Nuclear fusion is the merging of light atomic nuclei (e.g. hydrogen isotopes) into a heavier nucleus, also releasing energy. Both processes release large amounts of energy due to the mass defect according to Einstein's formula E=mc². Fission is used in nuclear power plants, fusion takes place in stars. Fusion requires extremely high temperatures and pressures. Both processes differ in requirements, products and hazards.
Nuclear fission splits heavy nuclei and releases energy as well as neutrons; nuclear fusion merges light nuclei into heavier ones while releasing energy. Both use the mass defect for energy production, but differ in conditions and applications.
An example
Which process takes place mainly in the Sun: nuclear fission or nuclear fusion?
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50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Physics. The topic assignment may vary by federal state.