Stellar spectra and the Hertzsprung–Russell diagram
Answers are for parents and teachers.
1
Hα is 656 nm, Hβ is 486 nm. The difference?
170
2
L ∝ M³·⁵: for M = 16 M☉, 16³·⁵ = 2¹⁴ = ? (2¹⁴ = 16,384)
16384
3
If m – M = 5 lg d – 5 = 10 then 5 lg d = 15, lg d = 3, d = ? pc
1000
4
Why does the Sun spend a long time on the main sequence?
Its hydrogen supply is large and fusion runs slowly and steadily (L is modest).
5
Where is a white dwarf on the diagram and why is it faint?
Lower left; hot, but its tiny radius gives low luminosity.