Physics A-Level
Neutron star
What Neutron star means in Physics A-Level, as defined for AQA, OCR.
Definitions of Neutron star
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Reference: OCR
The collapsed core left after a supernova, extremely dense, with a mass similar to the Sun packed into a radius of about 10 km, and supported against further collapse by neutron degeneracy pressure.
A collapsed core composed mainly of neutrons, with some protons and electrons, at nuclear density around 10¹⁷ kg m⁻³.
The remnant that forms if the mass of the collapsed core is below roughly three solar masses.
Topics that use Neutron star
- Supernovae, neutron stars and black holes (A-level only) (AQA A-Level)
- Stars (OCR A-Level)
Related terms
- Black hole
- Chandrasekhar limit
- Supernova
- Accretion
- Active galactic nuclei
- dark energy
- Electron degeneracy pressure
- Gravitational collapse
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