Question

on the h-r diagram, which star has a lower luminosity than the sun but a similar surface temperature?

1. betelgeuse
2. proxima centauri
3. 61 cygni a
4. rigel

Explanation:

To solve this, we analyze each star:

• Betelgeuse: Red supergiant, much cooler (lower temp) and more luminous than Sun.
• Proxima Centauri: Red dwarf, similar surface temp to Sun (around 5000–6000 K range for Sun, Proxima ~3000–4000 K but relatively close) and much lower luminosity (faint star).
• 61 Cygni A: More luminous than Sun, similar temp.
• Rigel: Blue supergiant, hotter and more luminous.

Proxima Centauri has lower luminosity than Sun but a surface temperature in a range somewhat similar (red dwarf vs Sun’s G-type, but closer than the others’ extremes).

Answer:

1. Proxima Centauri