AST 101: Lesson 10
Shown below here is the track on the H-R diagram of a star like the Sun.
At Point A the star is - correct answer ✔ ✔ fusing hydrogen in a
shell around a collapsing core.
Submit
From the same H-R diagram above, at Point B, the star is - correct
answer ✔ ✔ fusing helium in its core and hydrogen in a shell.
From the same H-R diagram above, at Point C, the star is - correct
answer ✔ ✔ has a stable, inert carbon core and essentially no
hydrogen or helium.
A supernova occurs when - correct answer ✔ ✔ a massive star fuses
through successively heavier elements until it has an iron core, which
will not release energy from fusion.
Consider a young globular star cluster where all the cluster stars formed
at about the same time. If you were to observe this star cluster over
, several billion years, you would see - correct answer ✔ ✔ many
supernovae early on, and then no more.
Why are red giant stars rare compared to main-sequence stars? - correct
answer ✔ ✔ The amount of time a red giant lasts is small compared
to the lifespan of a main-sequence star.
Why doesn't a high-mass star fuse its iron into heavier elements, like
uranium? - correct answer ✔ ✔ No mass-energy is released due to
the fusion of iron.
In the dying stages of our Sun, it will fuse helium into carbon. After that,
what will occur? - correct answer ✔ ✔ The core contracts, but the
carbon never fuses.
Listed following are characteristics that describe either high-mass or
low-mass stars. Match these characteristics to the appropriate category. -
correct answer ✔ ✔ High-mass stars:
late in-life fuse carbon into heavier elements
have higher fusion rate during main sequence life
end life as supernova
Low-mass stars:
Shown below here is the track on the H-R diagram of a star like the Sun.
At Point A the star is - correct answer ✔ ✔ fusing hydrogen in a
shell around a collapsing core.
Submit
From the same H-R diagram above, at Point B, the star is - correct
answer ✔ ✔ fusing helium in its core and hydrogen in a shell.
From the same H-R diagram above, at Point C, the star is - correct
answer ✔ ✔ has a stable, inert carbon core and essentially no
hydrogen or helium.
A supernova occurs when - correct answer ✔ ✔ a massive star fuses
through successively heavier elements until it has an iron core, which
will not release energy from fusion.
Consider a young globular star cluster where all the cluster stars formed
at about the same time. If you were to observe this star cluster over
, several billion years, you would see - correct answer ✔ ✔ many
supernovae early on, and then no more.
Why are red giant stars rare compared to main-sequence stars? - correct
answer ✔ ✔ The amount of time a red giant lasts is small compared
to the lifespan of a main-sequence star.
Why doesn't a high-mass star fuse its iron into heavier elements, like
uranium? - correct answer ✔ ✔ No mass-energy is released due to
the fusion of iron.
In the dying stages of our Sun, it will fuse helium into carbon. After that,
what will occur? - correct answer ✔ ✔ The core contracts, but the
carbon never fuses.
Listed following are characteristics that describe either high-mass or
low-mass stars. Match these characteristics to the appropriate category. -
correct answer ✔ ✔ High-mass stars:
late in-life fuse carbon into heavier elements
have higher fusion rate during main sequence life
end life as supernova
Low-mass stars:
