Question 1

By studying how the surface of the Sun vibrates like a struck bell we can determine its

Accepted Answer

A)  age. 
B)  interior density. 
C)  total mass. 
D)  size. 
E)  temperature. 
A)  age. 
B)  interior density. 
C)  total mass. 
D)  size. 
E)  temperature. B

Question 2

The energy that fuels the Sun is generated

Accepted Answer

A)  only on its surface. 
B)  only in its core. 
C)  only in the solar wind. 
D)  both in its core and on its surface. 
E)  in its core, on its surface, and in the solar wind. 
A)  only on its surface. 
B)  only in its core. 
C)  only in the solar wind. 
D)  both in its core and on its surface. 
E)  in its core, on its surface, and in the solar wind. B

Question 3

If the Sun was not currently in hydrostatic equilibrium, we would see

Accepted Answer

A)  more sunspots at all times. 
B)  more energetic solar flares. 
C)  the Sun's radius increasing or decreasing. 
D)  vastly more or fewer neutrinos than we detect. 
E)  the Sun's luminosity increasing or decreasing. 
A)  more sunspots at all times. 
B)  more energetic solar flares. 
C)  the Sun's radius increasing or decreasing. 
D)  vastly more or fewer neutrinos than we detect. 
E)  the Sun's luminosity increasing or decreasing. C

Question 4

Why is hydrogen fusion the main energy source for main-sequence stars? Give at least two reasons.

Accepted Answer

(1)Hydrogen is the most abundant element

Question 5

When, during its 11-year cycle, is the Sun most luminous? Given your answer, what effect on Earth might the Maunder Minimum have had?

Accepted Answer

The Sun is most luminous during solar ma

Question 6

When is the Sun most luminous?

Accepted Answer

A)  when there are a maximum number of sunspots 
B)  when there are an average number of sunspots 
C)  when there are a minimum number of sunspots 
D)  The Sun's luminosity does not change. 
E)  The Sun's luminosity changes, but it has no relation to the number of sunspots. 
A)  when there are a maximum number of sunspots 
B)  when there are an average number of sunspots 
C)  when there are a minimum number of sunspots 
D)  The Sun's luminosity does not change. 
E)  The Sun's luminosity changes, but it has no relation to the number of sunspots.

Question 7

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

Accepted Answer

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

Question 8

Astronauts in space could be harmed by the high-energy particles given off during a solar flare.When a solar flare is observed, a warning can be given to astronauts to tell them to get inside the space station for protection.Explain why there is enough time between the first observation of a flare and the arrival of the harmful particles for this system to work.

Accepted Answer

The first sign of a solar flare to arriv

Question 9

The magnetic field of the Sun is continuously produced and deformed by

Accepted Answer

A)  its differential rotation. 
B)  the solar wind. 
C)  changes in the rate of nuclear fusion in the core. 
D)  a liquid-conducting layer in the interior. 
E)  This is a trick question.The solar magnetic field is primordial. 
A)  its differential rotation. 
B)  the solar wind. 
C)  changes in the rate of nuclear fusion in the core. 
D)  a liquid-conducting layer in the interior. 
E)  This is a trick question.The solar magnetic field is primordial.

Question 10

The Sun's chromosphere appears red because

Accepted Answer

A)  it is hotter than the photosphere. 
B)  as the Sun rotates, the chromosphere appears to move away from us radially. 
C)  it has a higher concentration of heavy metals. 
D)  it is made of mostly helium. 
E)  its spectrum is dominated by H$\alpha$ emission. 
A)  it is hotter than the photosphere. 
B)  as the Sun rotates, the chromosphere appears to move away from us radially. 
C)  it has a higher concentration of heavy metals. 
D)  it is made of mostly helium. 
E)  its spectrum is dominated by H$\alpha$ emission.

Question 11

Which force is responsible for holding the protons and neutrons in the nucleus of an atom together?

Accepted Answer

A)  gravity 
B)  strong nuclear force 
C)  electric force 
D)  magnetic force 
E)  electrons pushing them together 
A)  gravity 
B)  strong nuclear force 
C)  electric force 
D)  magnetic force 
E)  electrons pushing them together

Question 12

The Sun's magnetic field reverses direction every

Accepted Answer

A)  24 hours. 
B)  27 days. 
C)  12 months. 
D)  11 years. 
E)  22 years. 
A)  24 hours. 
B)  27 days. 
C)  12 months. 
D)  11 years. 
E)  22 years.

Question 13

The density and temperature profiles of the solar atmosphere are shown in the figure below.Use these graphs to explain why scientists are justified in considering the chromosphere and corona to be distinct, separate layers.

Accepted Answer

From the graphs,there is clearly a sudde

Question 14

If you hold onto one end of a metal spoon after placing the other end in a pot of boiling water, you will burn your hand.This is an example of energy being transported by

Accepted Answer

A)  radiation. 
B)  convection. 
C)  conduction. 
D)  convection and radiation. 
E)  radiation and conduction. 
A)  radiation. 
B)  convection. 
C)  conduction. 
D)  convection and radiation. 
E)  radiation and conduction.

Question 15

The surface of the Sun appears sharp when we look at it in visible light because

Accepted Answer

A)  the photosphere is cooler than the layers below it. 
B)  the photosphere is thin compared with the other layers in the Sun. 
C)  the photosphere is much less dense than the convection zone. 
D)  its high luminosity provides plenty of photons, resulting in extreme definition. 
E)  the Sun has a distinct surface. 
A)  the photosphere is cooler than the layers below it. 
B)  the photosphere is thin compared with the other layers in the Sun. 
C)  the photosphere is much less dense than the convection zone. 
D)  its high luminosity provides plenty of photons, resulting in extreme definition. 
E)  the Sun has a distinct surface.

Question 16

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

Accepted Answer

A)  expand. 
B)  contract. 
C)  remain approximately the same. 
D)  repel charged particles. 
E)  block out sunlight. 
A)  expand. 
B)  contract. 
C)  remain approximately the same. 
D)  repel charged particles. 
E)  block out sunlight.

Question 17

Where does hydrostatic equilibrium exist in the Sun?

Accepted Answer

A)  only in the core, where energy production via fusion can balance gravity 
B)  in the outer layers of the atmosphere, where most of the visible light is produced 
C)  just outside the core, where heat from nuclear fusion is transported outward 
D)  throughout the Sun's interior. 
E)  only in the photosphere. 
A)  only in the core, where energy production via fusion can balance gravity 
B)  in the outer layers of the atmosphere, where most of the visible light is produced 
C)  just outside the core, where heat from nuclear fusion is transported outward 
D)  throughout the Sun's interior. 
E)  only in the photosphere.

Question 18

The interior zones of the Sun are distinguished by

Accepted Answer

A)  jumps in density between zones. 
B)  their temperature profiles. 
C)  pressure differences inside each zone. 
D)  their modes of energy production transport. 
E)  all of these. 
A)  jumps in density between zones. 
B)  their temperature profiles. 
C)  pressure differences inside each zone. 
D)  their modes of energy production transport. 
E)  all of these.

Question 19

The hottest layer of the solar atmosphere is the

Accepted Answer

A)  outer convection zone. 
B)  photosphere. 
C)  chromosphere. 
D)  corona. 
E)  solar wind. 
A)  outer convection zone. 
B)  photosphere. 
C)  chromosphere. 
D)  corona. 
E)  solar wind.

Question 20

Explain why it is impossible to find a stable main-sequence star that is much hotter than the Sun, but has the same mass, composition, radius, and luminosity as the Sun.

Accepted Answer

Due to requirements for hydrostatic equi

Exam 14: Our Starthe Sun

By studying how the surface of the Sun vibrates like a struck bell we can determine its

The energy that fuels the Sun is generated

If the Sun was not currently in hydrostatic equilibrium, we would see

Why is hydrogen fusion the main energy source for main-sequence stars? Give at least two reasons.

When, during its 11-year cycle, is the Sun most luminous? Given your answer, what effect on Earth might the Maunder Minimum have had?

When is the Sun most luminous?

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

The magnetic field of the Sun is continuously produced and deformed by

The Sun's chromosphere appears red because

Which force is responsible for holding the protons and neutrons in the nucleus of an atom together?

The Sun's magnetic field reverses direction every

The density and temperature profiles of the solar atmosphere are shown in the figure below.Use these graphs to explain why scientists are justified in considering the chromosphere and corona to be distinct, separate layers.

If you hold onto one end of a metal spoon after placing the other end in a pot of boiling water, you will burn your hand.This is an example of energy being transported by

The surface of the Sun appears sharp when we look at it in visible light because

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

Where does hydrostatic equilibrium exist in the Sun?

The interior zones of the Sun are distinguished by

The hottest layer of the solar atmosphere is the

Explain why it is impossible to find a stable main-sequence star that is much hotter than the Sun, but has the same mass, composition, radius, and luminosity as the Sun.

Thinking Like an Astronomer

Patterns in the Skymotions of Earth and the Moon

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Formation of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquidthe Giant Planets

Planetary Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

The Interstellar Medium and Star Formation

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

Relativity and Black Holes

Galaxies

The Milky Waya Normal Spiral Galaxy

The Expanding Universe

Cosmology

Large-Scale Structure in the Universe

Life

Filters