IB Physics HL E 5 4 Stellar Mass and Evolution Questions

Use HL stellar mass and luminosity evidence to estimate mass, trace HR-diagram evolution and compare the final stages of low- and high-mass stars.

Exam points

use the mass–luminosity relation to estimate stellar mass from luminosity relative to the Sun
trace likely evolutionary paths on an HR diagram and relate movement to changing stellar properties
compare low- and high-mass evolution, including red-giant or red-supergiant stages, planetary nebulae, white dwarfs and supernova outcomes

Learn this topic

Study E.5.4—Stellar mass and evolution conceptsOpen the corresponding Concept lesson for explanations, examples and exam connections.

[Maximum number: 3]

Alpha Centauri A and B form the closest binary star system to the Earth. This binary star system is the third brightest stellar object in the night sky.

(a)

Proxima Centauri is a main sequence star with a mass of $0.12 M_{\odot}$ .

Compare the times for which Proxima Centauri and Alpha Centauri A are main sequence stars.

[ 2 ]

$\ll \mathrm{L}=\mathrm{E} / \mathrm{t}$ and E proportional to M so >t inversely proportional to $M^{2.5}$
OR

Marking guidance:

Award [1] for a correct but incomplete reason, e.g. larger luminosity, or smaller
mass, with the correct conclusion.

$\frac{t_{P}}{t_{\alpha}}=\left(\frac{1.12}{0.12}\right)^{2.5}$

OR faster fusion rate to hydrogen available in Alpha Centauri A

Proxima Centauri stays longer on main sequence OR
$t_{P}=270 t_{\alpha}$

(b)

Explain the relationship between binary star systems and type I a supernovae.

[ 1 ]

All question bank results loaded

Learn this topic

IB Physics HL E 5 4 Stellar Mass and Evolution Questions question 1

Question (a)

Question (b)