absolute magnitude
What absolute magnitude means in Physics A-Level, as defined for AQA.
Definitions of absolute magnitude
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Reference: AQA
A logarithmic measure of luminosity shown on the vertical axis, typically spanning roughly –10 at the top to +15 at the bottom, with values increasing downwards.
A quantity plotted on the HR diagram which becomes more negative upwards, with the Sun at approximately +4.8 or +5.
Topics that use absolute magnitude
- The Hertzsprung-Russell (HR) diagram (A-level only) (AQA A-Level)
Related terms
- Giants and supergiants
- HR diagram
- Luminosity
- Main sequence
- Red giant branch
- Reversed temperature axis
- spectral class
- Surface temperature axis
Using absolute magnitude in the exam
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