Physics GCSE
iron as the limit
What iron as the limit means in Physics GCSE, as defined for AQA.
Definition of iron as the limit
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Reference: AQA
Fusing nuclei heavier than iron takes energy in rather than giving it out, so no star can make elements such as gold or uranium in its core.
Topics that use iron as the limit
- The life cycle of a star (AQA GCSE)
Related terms
- distribution of the elements
- neutron star or black hole
- nuclear fusion
- proton number defines the element
- supernova
- elements from a supernova
- extreme temperature and pressure
- how fusion works
Using iron as the limit in the exam
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