Physics A-Level
HR diagram
What HR diagram means in Physics A-Level, as defined for AQA, OCR.
Definitions of HR diagram
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Reference: AQA
A diagram plotting absolute magnitude against decreasing temperature, on which the Sun's position must align with the 5700 K and +5 marks.
A plot of luminosity on the vertical axis against temperature on the horizontal axis, with temperature increasing towards the left.
Topics that use HR diagram
- The Hertzsprung-Russell (HR) diagram (A-level only) (AQA A-Level)
- Stars (OCR A-Level)
Related terms
- Main sequence
- White dwarf
- White dwarfs
- absolute magnitude
- Black hole
- Chandrasekhar limit
- Electron degeneracy pressure
- Giants and supergiants
Using HR diagram in the exam
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