Question 1

The Sun will become a red giant star in about 2 billion years.

Accepted Answer

A) True 
 B)False

Question 2

Which point on the figure below represents the location on the H-R diagram where the star is expelling mass creating a planetary nebula?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
A)  A 
B)  B 
C)  C 
D)  D

Question 3

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?

Accepted Answer

The core of a low-mass main-sequence sta

Question 4

If a main-sequence star's core temperature increased,fusion reaction rates would decrease because the protons would be moving faster.

Accepted Answer

A) True 
 B)False

Question 5

The Sun eventually could become a nova.

Accepted Answer

A) True 
 B)False

Question 6

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

Accepted Answer

A)  rotational energy from the star's rapid rotation 
B)  heat released from the core's contraction 
C)  pressure from the contracting envelope 
D)  This is a trick question.Hydrogen actually burns increasingly slower with time 
A)  rotational energy from the star's rapid rotation 
B)  heat released from the core's contraction 
C)  pressure from the contracting envelope 
D)  This is a trick question.Hydrogen actually burns increasingly slower with time

Question 7

A main-sequence star is unique because:

Accepted Answer

A)  hydrostatic equilibrium exists at all radii 
B)  energy transport occurs via convection throughout much of its interior 
C)  hydrogen burning occurs in its core 
D)  it emits strong surface winds 
A)  hydrostatic equilibrium exists at all radii 
B)  energy transport occurs via convection throughout much of its interior 
C)  hydrogen burning occurs in its core 
D)  it emits strong surface winds

Question 8

The percent of hydrogen in the Sun's core today is roughly half of what it had originally.

Accepted Answer

A) True 
 B)False

Question 9

Which figure below represents the oldest star cluster?

Accepted Answer

A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D 
A)  Figure A 
B)  Figure B 
C)  Figure C 
D)  Figure D

Question 10

Why are novae thought to be recurrent?

Accepted Answer

The explosive hydrogen burning on the su

Question 11

A low-mass red giant star's energy comes from:

Accepted Answer

A)  hydrogen burning to helium in its core 
B)  helium burning to carbon in its core 
C)  hydrogen burning to helium in a shell surrounding its core 
D)  helium burning to carbon in a shell surrounding its core 
A)  hydrogen burning to helium in its core 
B)  helium burning to carbon in its core 
C)  hydrogen burning to helium in a shell surrounding its core 
D)  helium burning to carbon in a shell surrounding its core

Question 12

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

Accepted Answer

A helium nucleus has two protons and a n

Question 13

How many times longer does a 1.0 MS1U1B1$\bigodot$S1U1B0main-sequence star live compared to a 2.1 MS1U1B1$\bigodot$S1U1B0S1U1B0main-sequence star?

Accepted Answer

Main-sequence lifetime: 1.0 ×

Question 14

What factor is most important in determining a star's position on the main sequence and subsequent evolution?

Accepted Answer

A)  Temperature 
B)  Pressure 
C)  Mass 
D)  Radius 
A)  Temperature 
B)  Pressure 
C)  Mass 
D)  Radius

Question 15

Calculate the main-sequence lifetimes of the following stars of different spectral types: B0 (18 M$\bigodot$),B5 (6 M$\bigodot$),A5 (2 M$\bigodot$),F5 (1.3 M$\bigodot$),and M0 (0.5 M$\bigodot$).What trend do you notice in your results?

Accepted Answer

Main-sequence liftetime: @#LAT-DLM&_MS = 10¹⁰ yr × (M/M

Question 16

When helium fusion begins in the core of a red giant star,the situation quickly gets out of control because electron-degeneracy pressure does not respond to changes in:

Accepted Answer

A)  luminosity 
B)  density 
C)  gravity 
D)  temperature 
A)  luminosity 
B)  density 
C)  gravity 
D)  temperature

Question 17

Which point on the figure below represents the location on the H-R diagram where the star is on the horizontal branch?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
A)  A 
B)  B 
C)  C 
D)  D

Question 18

A 10 M$\bigodot$ star will evolve through the same phases as a 1 M$\bigodot$star.

Accepted Answer

A) True 
 B)False

Question 19

How can the core of a star be degenerate with respect to the electrons but nondegenerate with respect to the nuclei?

Accepted Answer

(1)Quantum mechanics says electrons take

Question 20

The more massive a star,the more hydrogen it has to burn,and the longer its main-sequence lifetime will be.

Accepted Answer

A) True 
 B)False

The Sun will become a red giant star in about 2 billion years.

Which point on the figure below represents the location on the H-R diagram where the star is expelling mass creating a planetary nebula?

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?

If a main-sequence star's core temperature increased,fusion reaction rates would decrease because the protons would be moving faster.

The Sun eventually could become a nova.

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

A main-sequence star is unique because:

The percent of hydrogen in the Sun's core today is roughly half of what it had originally.

Which figure below represents the oldest star cluster?

Why are novae thought to be recurrent?

A low-mass red giant star's energy comes from:

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

How many times longer does a 1.0 M_$\bigodot$main-sequence star live compared to a 2.1 M_$\bigodot$main-sequence star?

What factor is most important in determining a star's position on the main sequence and subsequent evolution?

Calculate the main-sequence lifetimes of the following stars of different spectral types: B0 (18 M_$\bigodot$),B5 (6 M_$\bigodot$),A5 (2 M_$\bigodot$),F5 (1.3 M_$\bigodot$),and M0 (0.5 M_$\bigodot$).What trend do you notice in your results?

When helium fusion begins in the core of a red giant star,the situation quickly gets out of control because electron-degeneracy pressure does not respond to changes in:

Which point on the figure below represents the location on the H-R diagram where the star is on the horizontal branch?

A 10 M_$\bigodot$ star will evolve through the same phases as a 1 M_$\bigodot$star.

How can the core of a star be degenerate with respect to the electrons but nondegenerate with respect to the nuclei?

The more massive a star,the more hydrogen it has to burn,and the longer its main-sequence lifetime will be.

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 Sun will become a red giant star in about 2 billion years.

Which point on the figure below represents the location on the H-R diagram where the star is expelling mass creating a planetary nebula?

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?

If a main-sequence star's core temperature increased,fusion reaction rates would decrease because the protons would be moving faster.

The Sun eventually could become a nova.

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

A main-sequence star is unique because:

The percent of hydrogen in the Sun's core today is roughly half of what it had originally.

Which figure below represents the oldest star cluster?

Why are novae thought to be recurrent?

A low-mass red giant star's energy comes from:

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

How many times longer does a 1.0 M ⨀\bigodot⨀ main-sequence star live compared to a 2.1 M ⨀\bigodot⨀ main-sequence star?

What factor is most important in determining a star's position on the main sequence and subsequent evolution?

Calculate the main-sequence lifetimes of the following stars of different spectral types: B0 (18 M ⨀\bigodot⨀ ),B5 (6 M ⨀\bigodot⨀ ),A5 (2 M ⨀\bigodot⨀ ),F5 (1.3 M ⨀\bigodot⨀ ),and M0 (0.5 M ⨀\bigodot⨀ ).What trend do you notice in your results?

When helium fusion begins in the core of a red giant star,the situation quickly gets out of control because electron-degeneracy pressure does not respond to changes in:

Which point on the figure below represents the location on the H-R diagram where the star is on the horizontal branch?

A 10 M ⨀\bigodot⨀ star will evolve through the same phases as a 1 M ⨀\bigodot⨀ star.

How can the core of a star be degenerate with respect to the electrons but nondegenerate with respect to the nuclei?

The more massive a star,the more hydrogen it has to burn,and the longer its main-sequence lifetime will be.

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

How many times longer does a 1.0 M_$\bigodot$main-sequence star live compared to a 2.1 M_$\bigodot$main-sequence star?

Calculate the main-sequence lifetimes of the following stars of different spectral types: B0 (18 M_$\bigodot$),B5 (6 M_$\bigodot$),A5 (2 M_$\bigodot$),F5 (1.3 M_$\bigodot$),and M0 (0.5 M_$\bigodot$).What trend do you notice in your results?

A 10 M_$\bigodot$ star will evolve through the same phases as a 1 M_$\bigodot$star.