The Life of a Star
2 marks · Easy| Star | Surface Temperature (K) | Absolute Magnitude |
|---|---|---|
| Alpha | 6,000 | +5 |
| Beta | 20,000 | -5 |
| Gamma | 3,500 | -1 |
Based on the data above, which star is the brightest and which is the coolest?
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Beta is the brightest (lowest magnitude), Gamma is the coolest (lowest temperature).
Also accept: Brightest: Beta; Coolest: Gamma
Common mistakes: Mixing up brightness and temperature
Show mark scheme and worked solution
Marking points
B1 · 1 mark · Identifies Beta as the brightest (lowest absolute magnitude).
B1 · 1 mark · Identifies Gamma as the coolest (lowest surface temperature).
Worked solution
Beta has the lowest (most negative) absolute magnitude, so it is the brightest. Gamma has the lowest temperature, so it is the coolest.