Fusion joins two light nuclei into a heavier one
Definition
Nuclear fusion
The joining of two light nuclei to form a heavier nucleus, in which some mass is converted into the energy of radiation.
- Nuclear fusion is when two light nuclei join together to form a single heavier nucleus.
- It is the opposite of fission, which splits one heavy nucleus into smaller pieces.
Some of the mass is converted into the energy of radiation
- In fusion some of the mass of the original nuclei is converted into energy.
- This energy is released as radiation.
- Fusion needs extremely high temperatures and pressures, because the two positively charged nuclei repel each other and must be forced very close together.
Note
- Fusion is the process that releases energy in the Sun and other stars.
Common Mistake
- Do not mix up fusion and fission: fusion joins two light nuclei, while fission splits one heavy nucleus.
Self review
- What is nuclear fusion?
- What happens to some of the mass of the nuclei during fusion?
- In what form is the energy released during fusion?
- Why does fusion need very high temperatures and pressures?
- How is fusion different from fission?
