Question 1

The gas in a planetary nebula is composed of:

Accepted Answer

A)  primarily hydrogen from the surrounding interstellar medium 
B)  primarily hydrogen from the post-asymptotic giant branch star 
C)  hydrogen and elements processed in the core of the post-asymptotic giant branch star 
D)  primarily helium from the post-asymptotic giant branch star 
A)  primarily hydrogen from the surrounding interstellar medium 
B)  primarily hydrogen from the post-asymptotic giant branch star 
C)  hydrogen and elements processed in the core of the post-asymptotic giant branch star 
D)  primarily helium from the post-asymptotic giant branch star

Question 2

A Type Ia supernova is as luminous as 10 billion Suns.

Accepted Answer

A) True 
 B)False

Question 3

Asymptotic giant branch (AGB)stars have high-mass loss rates because:

Accepted Answer

A)  they are rotating quickly 
B)  they have weak magnetic fields 
C)  they have strong winds 
D)  they have low surface gravity 
A)  they are rotating quickly 
B)  they have weak magnetic fields 
C)  they have strong winds 
D)  they have low surface gravity

Question 4

The luminosity of a star depends on:

Accepted Answer

A)  its mass,its age,and its distance 
B)  its mass 
C)  its age 
D)  its mass and its age 
A)  its mass,its age,and its distance 
B)  its mass 
C)  its age 
D)  its mass and its age

Question 5

Pressure from degenerate electrons keeps the core of a red giant star from collapsing.

Accepted Answer

A) True 
 B)False

Question 6

Suppose you measured H-R diagrams for the two star clusters pictured below.   Which of the following statements is TRUE?

Accepted Answer

A)  Cluster A is younger than Cluster B. 
B)  Cluster A is closer to us than Cluster B. 
C)  Both a and b are TRUE. 
D)  Both a and b are FALSE. 
A)  Cluster A is younger than Cluster B. 
B)  Cluster A is closer to us than Cluster B. 
C)  Both a and b are TRUE. 
D)  Both a and b are FALSE.

Question 7

When a G2 star leaves the main sequence:

Accepted Answer

A)  its luminosity and surface temperature both stay the same 
B)  its luminosity and surface temperature both decrease 
C)  its luminosity increases and its surface temperature decreases 
D)  its luminosity and surface temperature both increase 
A)  its luminosity and surface temperature both stay the same 
B)  its luminosity and surface temperature both decrease 
C)  its luminosity increases and its surface temperature decreases 
D)  its luminosity and surface temperature both increase

Question 8

Describe the triple-alpha process of nuclear fusion?

Accepted Answer

The triple-alpha process is a two-stage

Question 9

Why does helium burning in the core of a giant star not cause the star to become more luminous?

Accepted Answer

The nuclear reaction rate in t

Question 10

As a main-sequence star burns its core supply of hydrogen,what happens?

Accepted Answer

A)  Helium begins to fuse throughout the core. 
B)  Helium fuses in a shell surrounding the core. 
C)  Helium fusion takes place only at the very center of the core,where temperature and pressure are highest. 
D)  Helium builds up as ash in the core. 
A)  Helium begins to fuse throughout the core. 
B)  Helium fuses in a shell surrounding the core. 
C)  Helium fusion takes place only at the very center of the core,where temperature and pressure are highest. 
D)  Helium builds up as ash in the core.

Question 11

What ionizes the gas in a planetary nebula (see the image below)and makes it visible?

Accepted Answer

A)  X-ray photons emitted by a pulsar 
B)  Ultraviolet photons emitted by a white dwarf 
C)  The shock wave from a supernova 
D)  Hydrogen burning in the nebular gas 
A)  X-ray photons emitted by a pulsar 
B)  Ultraviolet photons emitted by a white dwarf 
C)  The shock wave from a supernova 
D)  Hydrogen burning in the nebular gas

Question 12

A star like the Sun will eventually become an electron degenerate white dwarf star.

Accepted Answer

A) True 
 B)False

Question 13

Suppose you observe three star clusters.Cluster 1 has a main-sequence turnoff point at spectral type G,Cluster 2 has a turnoff point at spectral type A,and Cluster 3 has a turnoff point at spectral type B.Which cluster is youngest and which is oldest? Explain why.What is the approximate age of the oldest cluster?

Accepted Answer

Of the three types of main-sequence turn

Question 14

The figure below plots the chemical composition of the Sun as a function of radius for three different times.Which graph represents the correct chemical composition just prior to the Sun becoming a red giant?

Accepted Answer

A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  No figure is correct 
A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  No figure is correct

Question 15

A low-mass star that burns helium in its core and hydrogen in a shell is more luminous than a similar star that burns only hydrogen in a shell around a dead core.

Accepted Answer

A) True 
 B)False

Question 16

In what two ways does temperature affect the rate of nuclear reactions?

Accepted Answer

Higher temperature means atomic nuclei a

Question 17

A star like the Sun will lose about __________ of its mass before it evolves to become a white dwarf.

Accepted Answer

A)  3 percent 
B)  10 percent 
C)  30 percent 
D)  70 percent 
A)  3 percent 
B)  10 percent 
C)  30 percent 
D)  70 percent

Question 18

A Type Ia supernova has a luminosity of approximately:

Accepted Answer

A)  10 thousand L$\bigodot$ 
B)  10 million L$\bigodot$ 
C)  10 billion L$\bigodot$ 
D)  10 trillion L$\bigodot$ 
A)  10 thousand L$\bigodot$ 
B)  10 million L$\bigodot$ 
C)  10 billion L$\bigodot$ 
D)  10 trillion L$\bigodot$

Question 19

Once the core of a low-mass main-sequence star runs out of hydrogen,fusion in the star stops until the core temperature is high enough for helium fusion to begin.

Accepted Answer

A) True 
 B)False

Question 20

A Type Ia supernova occurs when a white dwarf exceeds a mass of __________.

Accepted Answer

A)  0.8 M$\bigodot$ 
B)  1.4 M$\bigodot$ 
C)  2.3 M$\bigodot$ 
D)  5.5 M$\bigodot$ 
A)  0.8 M$\bigodot$ 
B)  1.4 M$\bigodot$ 
C)  2.3 M$\bigodot$ 
D)  5.5 M$\bigodot$

The gas in a planetary nebula is composed of:

A Type Ia supernova is as luminous as 10 billion Suns.

Asymptotic giant branch (AGB)stars have high-mass loss rates because:

The luminosity of a star depends on:

Pressure from degenerate electrons keeps the core of a red giant star from collapsing.

Suppose you measured H-R diagrams for the two star clusters pictured below. Which of the following statements is TRUE?

When a G2 star leaves the main sequence:

Describe the triple-alpha process of nuclear fusion?

Why does helium burning in the core of a giant star not cause the star to become more luminous?

As a main-sequence star burns its core supply of hydrogen,what happens?

What ionizes the gas in a planetary nebula (see the image below)and makes it visible?

A star like the Sun will eventually become an electron degenerate white dwarf star.

The figure below plots the chemical composition of the Sun as a function of radius for three different times.Which graph represents the correct chemical composition just prior to the Sun becoming a red giant?

A low-mass star that burns helium in its core and hydrogen in a shell is more luminous than a similar star that burns only hydrogen in a shell around a dead core.

In what two ways does temperature affect the rate of nuclear reactions?

A star like the Sun will lose about __________ of its mass before it evolves to become a white dwarf.

A Type Ia supernova has a luminosity of approximately:

Once the core of a low-mass main-sequence star runs out of hydrogen,fusion in the star stops until the core temperature is high enough for helium fusion to begin.

A Type Ia supernova occurs when a white dwarf exceeds a mass of __________.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of High-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

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Exam 12: Evolution of Low-Mass Stars

The gas in a planetary nebula is composed of:

A Type Ia supernova is as luminous as 10 billion Suns.

Asymptotic giant branch (AGB)stars have high-mass loss rates because:

The luminosity of a star depends on:

Pressure from degenerate electrons keeps the core of a red giant star from collapsing.

Suppose you measured H-R diagrams for the two star clusters pictured below. Which of the following statements is TRUE?

When a G2 star leaves the main sequence:

Describe the triple-alpha process of nuclear fusion?

Why does helium burning in the core of a giant star not cause the star to become more luminous?

As a main-sequence star burns its core supply of hydrogen,what happens?

What ionizes the gas in a planetary nebula (see the image below)and makes it visible?

A star like the Sun will eventually become an electron degenerate white dwarf star.

The figure below plots the chemical composition of the Sun as a function of radius for three different times.Which graph represents the correct chemical composition just prior to the Sun becoming a red giant?

A low-mass star that burns helium in its core and hydrogen in a shell is more luminous than a similar star that burns only hydrogen in a shell around a dead core.

In what two ways does temperature affect the rate of nuclear reactions?

A star like the Sun will lose about __________ of its mass before it evolves to become a white dwarf.

A Type Ia supernova has a luminosity of approximately:

Once the core of a low-mass main-sequence star runs out of hydrogen,fusion in the star stops until the core temperature is high enough for helium fusion to begin.

A Type Ia supernova occurs when a white dwarf exceeds a mass of __________.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of High-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters