Exam 16: Evolution of Low-Mass Stars

The figure below depicts the evolution in chemical composition of the Sun's interior at three different times during its life.How do the relative percentages of hydrogen and helium change at a fractional radius of 0.1 solar radii, from the time the Sun formed until it exhausts its core supply of hydrogen in 5 billion years?

A 1-M_SUN red giant star's energy comes from

As a star evolves through its post-main-sequence phases, what effect might be had on planets orbiting this star?

Why does the core of a main-sequence star have to be hotter to burn helium into carbon than hydrogen into helium?

What ionizes the gas in a planetary nebula and makes it visible?

A Type Ia supernova can be as luminous as

Novae and Type Ia supernovae can occur in binary star systems because ________ can mean large differences in their ________.

The ________ a main-sequence star is, the more hydrogen it has to burn, and the ________ its main-sequence lifetime.

Considering how long it took for life to arise on Earth, which of the stellar spectral types shown below would be the LEAST likely to have planets with life?

The Sun will become a red giant star in about

In a white dwarf, what is the source of pressure that halts its contraction as it cools?

As a red giant star evolves, hydrogen shell burning proceeds increasingly faster due to

Consider a 1 M_SUN star's journey up the red giant branch.Its luminosity will change from 10 L_SUN to nearly 1,000 L_SUN.How will its temperature and radius change as the star ascends? (Recall that L R²T⁴.)

What causes a star to leave the red giant phase and settle on the horizontal branch?

Explain the two different forms of pressure that support the core of a low-mass main-sequence star and the core of a low-mass red giant star.

The figure below depicts helium fusion in a late-stage star with certain elements labeled A, B, and C.What are these elements, in the order A, B, C?

Using the figure shown below, identify the star with the smallest radius.

What types of stars cause Type Ia supernovae, and what makes them explode?

A star like the Sun will eventually become a(n) ________ star.

How many times longer does a 2 M_SUN main-sequence star live compared to a 10 M_SUN main-sequence star?