Question 1

Illustrate the steps by which hydrogen is fused into helium in the Sun in the proton-proton chain.

Accepted Answer

In the first step,colliding protons crea

Question 2

If a sunspot appears one-third as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Accepted Answer

A)  4100 K 
B)  4400 K 
C)  5200 K 
D)  5500 K 
A)  4100 K 
B)  4400 K 
C)  5200 K 
D)  5500 K

Question 3

Explain why hydrostatic equilibrium results in the center of the Sun having the highest pressure and temperature.

Accepted Answer

Hydrostatic equilibrium means that,at an

Question 4

Detection of solar neutrinos confirms that:

Accepted Answer

A)  the Sun's core is powered by proton-proton fusion. 
B)  transport by radiation occurs throughout much of the solar interior. 
C)  magnetic fields are responsible for surface activity on the Sun. 
D)  convection churns the base of the solar atmosphere. 
A)  the Sun's core is powered by proton-proton fusion. 
B)  transport by radiation occurs throughout much of the solar interior. 
C)  magnetic fields are responsible for surface activity on the Sun. 
D)  convection churns the base of the solar atmosphere.

Question 5

When solar activity is very high,Earth's atmosphere will:

Accepted Answer

A)  expand. 
B)  contract. 
C)  remain approximately the same. 
D)  repel charged particles. 
A)  expand. 
B)  contract. 
C)  remain approximately the same. 
D)  repel charged particles.

Question 6

Which of the following are manifestations of solar magnetic activity?

Accepted Answer

A)  sunspots 
B)  prominences 
C)  flares 
D)  all of the above 
A)  sunspots 
B)  prominences 
C)  flares 
D)  all of the above

Question 7

Which of the following layers of the Sun makes up the majority of its interior?

Accepted Answer

A)  the core 
B)  the radiative zone 
C)  the convective zone 
D)  the photosphere 
A)  the core 
B)  the radiative zone 
C)  the convective zone 
D)  the photosphere

Question 8

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

Accepted Answer

If the temperature is higher,more energy

Question 9

The bulk of the Sun's energy generation is contained within a region of:

Accepted Answer

A)  0.2 solar radii. 
B)  0.5 solar radii. 
C)  0.75 solar radii. 
D)  1.0 solar radii. 
A)  0.2 solar radii. 
B)  0.5 solar radii. 
C)  0.75 solar radii. 
D)  1.0 solar radii.

Question 10

Approximately what is the temperature at the center of the Sun?

Accepted Answer

A)  1500 K 
B)  15,000 K 
C)  15 million K 
D)  15 billion K 
A)  1500 K 
B)  15,000 K 
C)  15 million K 
D)  15 billion K

Question 11

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

Accepted Answer

Gamma-ray radiation travels only short p

Question 12

When two atomic nuclei come together to form a new species of atom,it is called:

Accepted Answer

A)  nuclear fission. 
B)  nuclear fusion. 
C)  nuclear splitting. 
D)  nuclear recombination. 
A)  nuclear fission. 
B)  nuclear fusion. 
C)  nuclear splitting. 
D)  nuclear recombination.

Question 13

In the figure below,label the regions of the Sun.

Accepted Answer

The inner region is the core,t

Question 14

Density,temperature,and pressure ________ as you move inward in the interior of the Sun.

Accepted Answer

A)  increase 
B)  decrease 
C)  stay the same 
D)  There is not enough information provided. 
A)  increase 
B)  decrease 
C)  stay the same 
D)  There is not enough information provided.

Question 15

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg.)

Accepted Answer

The total amount of mass lost is
4,000 ×

Question 16

Why is hydrogen burning the main energy source for main-sequence stars?

Accepted Answer

A)  Hydrogen is the most common element in stars. 
B)  Hydrogen nuclei have the smallest positive charge. 
C)  Hydrogen burning is the most efficient of all fusion or fission reactions. 
D)  All the above are valid reasons. 
A)  Hydrogen is the most common element in stars. 
B)  Hydrogen nuclei have the smallest positive charge. 
C)  Hydrogen burning is the most efficient of all fusion or fission reactions. 
D)  All the above are valid reasons.

Question 17

The majority of the Sun's energy comes from:

Accepted Answer

A)  gravitational contraction. 
B)  its rapid rotation. 
C)  hydrogen fusion. 
D)  helium burning. 
A)  gravitational contraction. 
B)  its rapid rotation. 
C)  hydrogen fusion. 
D)  helium burning.

Question 18

Observations of sunspots led to the discovery of the Sun's:

Accepted Answer

A)  coronal holes. 
B)  coronal mass ejections. 
C)  differential rotation. 
D)  all of the above 
A)  coronal holes. 
B)  coronal mass ejections. 
C)  differential rotation. 
D)  all of the above

Question 19

Explain why magnetic fields trap coronal gas over much of the solar surface but allow it to escape in coronal holes.

Accepted Answer

Most of the solar magnetic field consist

Question 20

We can determine how the density changes with radius in the Sun using:

Accepted Answer

A)  radar observations. 
B)  neutrino detections. 
C)  high-energy (gamma ray) observations. 
D)  helioseismology. 
A)  radar observations. 
B)  neutrino detections. 
C)  high-energy (gamma ray) observations. 
D)  helioseismology.

Illustrate the steps by which hydrogen is fused into helium in the Sun in the proton-proton chain.

If a sunspot appears one-third as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Explain why hydrostatic equilibrium results in the center of the Sun having the highest pressure and temperature.

Detection of solar neutrinos confirms that:

When solar activity is very high,Earth's atmosphere will:

Which of the following are manifestations of solar magnetic activity?

Which of the following layers of the Sun makes up the majority of its interior?

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

The bulk of the Sun's energy generation is contained within a region of:

Approximately what is the temperature at the center of the Sun?

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

When two atomic nuclei come together to form a new species of atom,it is called:

In the figure below,label the regions of the Sun.

Density,temperature,and pressure ________ as you move inward in the interior of the Sun.

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg.)

Why is hydrogen burning the main energy source for main-sequence stars?

The majority of the Sun's energy comes from:

Observations of sunspots led to the discovery of the Sun's:

Explain why magnetic fields trap coronal gas over much of the solar surface but allow it to escape in coronal holes.

We can determine how the density changes with radius in the Sun using:

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

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

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Measuring Galaxies

Our Galaxy: the Milky Way

The Evolution of the Universe

Formation of Structure

Life in the Universe

Filters

Exam 11: Our Star: the Sun

Illustrate the steps by which hydrogen is fused into helium in the Sun in the proton-proton chain.

If a sunspot appears one-third as bright as the surrounding photosphere,and the average temperature of the photosphere is 5800 K,what is the temperature of the gas in this sunspot?

Explain why hydrostatic equilibrium results in the center of the Sun having the highest pressure and temperature.

Detection of solar neutrinos confirms that:

When solar activity is very high,Earth's atmosphere will:

Which of the following are manifestations of solar magnetic activity?

Which of the following layers of the Sun makes up the majority of its interior?

Show that a star with the same mass,composition,radius,and luminosity as the Sun,but with a higher temperature (that is,a "too-hot" Sun),leads to a contradiction.

The bulk of the Sun's energy generation is contained within a region of:

Approximately what is the temperature at the center of the Sun?

Examine the figure below.Explain why it takes so long for gamma-ray energy to find its way to the outer layers of the Sun.

When two atomic nuclei come together to form a new species of atom,it is called:

In the figure below,label the regions of the Sun.

Density,temperature,and pressure ________ as you move inward in the interior of the Sun.

Through hydrogen fusion,the Sun loses approximately 4 million tons of mass each second.If it burns hydrogen at this rate for 10 billion years,what percentage of its original mass will it lose in all? (Note: The mass of the Sun is 1.99 × 10³⁰ kg,and 1 ton = 1,000 kg.)

Why is hydrogen burning the main energy source for main-sequence stars?

The majority of the Sun's energy comes from:

Observations of sunspots led to the discovery of the Sun's:

Explain why magnetic fields trap coronal gas over much of the solar surface but allow it to escape in coronal holes.

We can determine how the density changes with radius in the Sun using:

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

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

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Measuring Galaxies

Our Galaxy: the Milky Way

The Evolution of the Universe

Formation of Structure

Life in the Universe

Filters