Question 1

Briefly describe the Sun's 22 year activity cycle.

Accepted Answer

The Sun's activity cycle is tied directl

Question 2

Gravitational equilibrium means that the surface and the core of the Sun are at the same pressure.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following quantities is equal to the energy per second generated by the Sun's nuclear reactions?

Accepted Answer

A)  The temperature of the Sun's core 
B)  The temperature at the Sun's photosphere 
C)  The force of gravity holding the Sun together 
D)  The luminosity of the Sun's photosphere 
A)  The temperature of the Sun's core 
B)  The temperature at the Sun's photosphere 
C)  The force of gravity holding the Sun together 
D)  The luminosity of the Sun's photosphere

Question 4

Interdisciplinary Science: Significant advancements in science often occur when several separate and distinct scientific disciplines come together to address a single question. Use the search for the Sun's energy source as a case study. Outline how astronomy and physics were driven to consider new possibilities for the Sun's energy by the fields of geology and biology.

Accepted Answer

The search for the Sun's energy source i

Question 5

Which of the following is not a characteristic of the 11-year sunspot cycle?

Accepted Answer

A)  The sunspot cycle is very steady, so that each 11-year cycle is nearly identical to every other 11-year cycle. 
B)  The likelihood of seeing solar prominences or solar flares is higher when sunspots are more common and lower when they are less common. 
C)  The Sun's entire magnetic field flip-flops with each cycle, so that the overall magnetic cycle averages 22 years. 
D)  The number of sunspots on the Sun at any one time gradually rises and falls, with an average of 11 years between the times when sunspots are most numerous. 
A)  The sunspot cycle is very steady, so that each 11-year cycle is nearly identical to every other 11-year cycle. 
B)  The likelihood of seeing solar prominences or solar flares is higher when sunspots are more common and lower when they are less common. 
C)  The Sun's entire magnetic field flip-flops with each cycle, so that the overall magnetic cycle averages 22 years. 
D)  The number of sunspots on the Sun at any one time gradually rises and falls, with an average of 11 years between the times when sunspots are most numerous.

Question 6

Which of the following processes is involved in the sunspot cycle?

Accepted Answer

A)  A slight gravitational contraction of the Sun 
B)  Small variations in the rate of nuclear energy generation in the solar interior 
C)  An imbalance in the operation of the solar thermostat 
D)  The winding of magnetic field lines due to the Sun's rotation 
E)  A large change in the amount of visible light emitted by the Sun 
A)  A slight gravitational contraction of the Sun 
B)  Small variations in the rate of nuclear energy generation in the solar interior 
C)  An imbalance in the operation of the solar thermostat 
D)  The winding of magnetic field lines due to the Sun's rotation 
E)  A large change in the amount of visible light emitted by the Sun

Question 7

How do we know how old the Sun is?

Accepted Answer

A)  From ages of solar system meteorites, based on radioactive elements 
B)  From Newton's version of Kepler's third law and the orbits of the planets 
C)  From calculating its fuel supply and how fast it is using it up 
D)  From its speed and distance from us 
A)  From ages of solar system meteorites, based on radioactive elements 
B)  From Newton's version of Kepler's third law and the orbits of the planets 
C)  From calculating its fuel supply and how fast it is using it up 
D)  From its speed and distance from us

Question 8

List at least two ways the sunspot cycle affects us on the Earth.

Accepted Answer

When the Sun is near solar maximum, it u

Question 9

The proton-proton chain is ________.

Accepted Answer

A)  the specific set of nuclear reactions through which the Sun fuses hydrogen into helium 
B)  the linkage of numerous protons into long chains 
C)  another name for the force that holds protons together in atomic nuclei 
D)  an alternative way of generating energy that is different from the fusion of hydrogen into helium 
A)  the specific set of nuclear reactions through which the Sun fuses hydrogen into helium 
B)  the linkage of numerous protons into long chains 
C)  another name for the force that holds protons together in atomic nuclei 
D)  an alternative way of generating energy that is different from the fusion of hydrogen into helium

Question 10

How does the Sun's mass compare to Earth's mass?

Accepted Answer

A)  The Sun's mass is about 300,000 times the mass of the Earth. 
B)  The Sun's mass is about 300 times the mass of the Earth. 
C)  The Sun's mass is about 30 times the mass of the Earth. 
D)  Both have approximately the same mass. 
A)  The Sun's mass is about 300,000 times the mass of the Earth. 
B)  The Sun's mass is about 300 times the mass of the Earth. 
C)  The Sun's mass is about 30 times the mass of the Earth. 
D)  Both have approximately the same mass.

Question 11

Which of the following is the phase of matter in the Sun?

Accepted Answer

A)  gas 
B)  plasma 
C)  liquid 
D)  solid 
E)  a mixture of all of the above 
A)  gas 
B)  plasma 
C)  liquid 
D)  solid 
E)  a mixture of all of the above

Question 12

Which of the following is not a method astronomers use to determine the physical conditions inside the Sun?

Accepted Answer

A)  Observing X-ray images of the solar interior using satellites. 
B)  Building mathematical models that use the laws of physics. 
C)  Detecting solar neutrinos generated in the Sun's core. 
D)  Measuring Doppler shifts to observe solar vibrations. 
E)  both C and D 
A)  Observing X-ray images of the solar interior using satellites. 
B)  Building mathematical models that use the laws of physics. 
C)  Detecting solar neutrinos generated in the Sun's core. 
D)  Measuring Doppler shifts to observe solar vibrations. 
E)  both C and D

Question 13

When is/was gravitational contraction an important energy generation mechanism for the Sun?

Accepted Answer

A)  It was important when the Sun was forming from a shrinking interstellar cloud of gas. 
B)  It is the primary energy generation mechanism in the Sun today. 
C)  It has played a role throughout the Sun's history, but it was most important right after nuclear fusion began in the Sun's core. 
D)  It is important during periods when the Sun is going from solar maximum to solar minimum. 
A)  It was important when the Sun was forming from a shrinking interstellar cloud of gas. 
B)  It is the primary energy generation mechanism in the Sun today. 
C)  It has played a role throughout the Sun's history, but it was most important right after nuclear fusion began in the Sun's core. 
D)  It is important during periods when the Sun is going from solar maximum to solar minimum.

Question 14

How can we best observe the Sun's chromosphere and corona?

Accepted Answer

A)  The chromosphere is best observed with ultraviolet telescopes and the corona is best observed with X-ray telescopes. 
B)  The chromosphere is best observed with infrared telescopes and the corona is best observed with ultraviolet telescopes. 
C)  The chromosphere and corona are both best studied with visible light. 
D)  The chromosphere and corona are both best studied with radio telescopes. 
A)  The chromosphere is best observed with ultraviolet telescopes and the corona is best observed with X-ray telescopes. 
B)  The chromosphere is best observed with infrared telescopes and the corona is best observed with ultraviolet telescopes. 
C)  The chromosphere and corona are both best studied with visible light. 
D)  The chromosphere and corona are both best studied with radio telescopes.

Question 15

By what process do nuclear power plants on the Earth generate energy?

Accepted Answer

A)  nuclear fission 
B)  nuclear fusion 
C)  chemical reactions 
D)  converting kinetic energy into electricity 
E)  converting gravitational potential energy into electricity 
A)  nuclear fission 
B)  nuclear fusion 
C)  chemical reactions 
D)  converting kinetic energy into electricity 
E)  converting gravitational potential energy into electricity

Question 16

The core of the Sun is

Accepted Answer

A)  at the same temperature and density as its surface. 
B)  at the same temperature but much denser than its surface. 
C)  much hotter and much denser than its surface. 
D)  constantly rising to the surface through convection. 
E)  composed of iron. 
A)  at the same temperature and density as its surface. 
B)  at the same temperature but much denser than its surface. 
C)  much hotter and much denser than its surface. 
D)  constantly rising to the surface through convection. 
E)  composed of iron.

Question 17

The Sun's average surface (photosphere) temperature is about ________.

Accepted Answer

A)  5,800 K 
B)  1,000,000 K 
C)  1,000 K 
D)  37,000 K 
A)  5,800 K 
B)  1,000,000 K 
C)  1,000 K 
D)  37,000 K

Question 18

Energy balance in the Sun refers to a balance between ________.

Accepted Answer

A)  the rate at which fusion generates energy in the Sun's core and the rate at which the Sun's surface radiates energy into space 
B)  the mass that the Sun loses each second and the amount of mass converted into energy each second 
C)  the force of gravity pulling inward and the force due to pressure pushing outward 
D)  the amount of energy the Sun radiates into space and the amount of energy that reaches Earth 
A)  the rate at which fusion generates energy in the Sun's core and the rate at which the Sun's surface radiates energy into space 
B)  the mass that the Sun loses each second and the amount of mass converted into energy each second 
C)  the force of gravity pulling inward and the force due to pressure pushing outward 
D)  the amount of energy the Sun radiates into space and the amount of energy that reaches Earth

Question 19

The proton-proton chain converts four hydrogen nuclei into one helium nucleus plus energy.

Accepted Answer

A) True 
 B)False

Question 20

Satellites in low-Earth orbits are more likely to crash to Earth when the sunspot cycle is near solar maximum because ________.

Accepted Answer

A)  it is too dangerous to send the Space Shuttle to service satellites during solar maximum 
B)  Earth's upper atmosphere tends to expand during solar maximum, exerting drag on satellites in low orbits 
C)  of increased magnetic interference 
D)  they are more likely to have their electronics "fried" by a solar flare during solar maximum 
A)  it is too dangerous to send the Space Shuttle to service satellites during solar maximum 
B)  Earth's upper atmosphere tends to expand during solar maximum, exerting drag on satellites in low orbits 
C)  of increased magnetic interference 
D)  they are more likely to have their electronics "fried" by a solar flare during solar maximum

Briefly describe the Sun's 22 year activity cycle.

Gravitational equilibrium means that the surface and the core of the Sun are at the same pressure.

Which of the following quantities is equal to the energy per second generated by the Sun's nuclear reactions?

Which of the following is not a characteristic of the 11-year sunspot cycle?

Which of the following processes is involved in the sunspot cycle?

How do we know how old the Sun is?

List at least two ways the sunspot cycle affects us on the Earth.

The proton-proton chain is ________.

How does the Sun's mass compare to Earth's mass?

Which of the following is the phase of matter in the Sun?

Which of the following is not a method astronomers use to determine the physical conditions inside the Sun?

When is/was gravitational contraction an important energy generation mechanism for the Sun?

How can we best observe the Sun's chromosphere and corona?

By what process do nuclear power plants on the Earth generate energy?

The core of the Sun is

The Sun's average surface (photosphere) temperature is about ________.

Energy balance in the Sun refers to a balance between ________.

The proton-proton chain converts four hydrogen nuclei into one helium nucleus plus energy.

Satellites in low-Earth orbits are more likely to crash to Earth when the sunspot cycle is near solar maximum because ________.

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Surveying the Stars

Star Stuff

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Life in the Universe

Filters

Exam 10: Our Star

Briefly describe the Sun's 22 year activity cycle.

Gravitational equilibrium means that the surface and the core of the Sun are at the same pressure.

Which of the following quantities is equal to the energy per second generated by the Sun's nuclear reactions?

Which of the following is not a characteristic of the 11-year sunspot cycle?

Which of the following processes is involved in the sunspot cycle?

How do we know how old the Sun is?

List at least two ways the sunspot cycle affects us on the Earth.

The proton-proton chain is ________.

How does the Sun's mass compare to Earth's mass?

Which of the following is the phase of matter in the Sun?

Which of the following is not a method astronomers use to determine the physical conditions inside the Sun?

When is/was gravitational contraction an important energy generation mechanism for the Sun?

How can we best observe the Sun's chromosphere and corona?

By what process do nuclear power plants on the Earth generate energy?

The core of the Sun is

The Sun's average surface (photosphere) temperature is about ________.

Energy balance in the Sun refers to a balance between ________.

The proton-proton chain converts four hydrogen nuclei into one helium nucleus plus energy.

Satellites in low-Earth orbits are more likely to crash to Earth when the sunspot cycle is near solar maximum because ________.

Our Place in the Universe

Discovering the Universe for Yourself

The Science of Astronomy

Making Sense of the Universe: Understanding Motion, Energy, and Gravity

Light: the Cosmic Messenger

Formation of Planetary Systems: Our Solar System and Beyond

Earth and the Terrestrial Worlds

Jovian Planet Systems

Asteroids, Comets, and Dwarf Planets: Their Nature, Orbits, and Impacts

Surveying the Stars

Star Stuff

Bizarre Stellar Graveyard

Our Galaxy

Galaxies and the Foundation of Modern Cosmology

Dark Matter, Dark Energy, and the Fate of the Universe

The Beginning of Time

Life in the Universe

Filters