Question 1

If the Sun collapsed to become a black hole,the Earth's gravitational attraction to it would be

Accepted Answer

A) more. 
B) less. 
C) no different. 
A) more. 
B) less. 
C) no different.

Question 2

Polaris is always directly overhead at

Accepted Answer

A) the north pole. 
B) any location north of the equator. 
C) the equator. 
A) the north pole. 
B) any location north of the equator. 
C) the equator.

Question 3

What will be the predominant element within the Sun after it has died?

Accepted Answer

A) helium 
B) nitrogen 
C) carbon 
D) phosphorous 
A) helium 
B) nitrogen 
C) carbon 
D) phosphorous

Question 4

A black hole has

Accepted Answer

A) about the same mass as the original star from which it formed. 
B) infinite mass. 
C) about half the mass of the star from which it formed. 
D) a mass that widely fluctuates. 
A) about the same mass as the original star from which it formed. 
B) infinite mass. 
C) about half the mass of the star from which it formed. 
D) a mass that widely fluctuates.

Question 5

Which best describes the intrinsic motion of stars?

Accepted Answer

A) their circular motion across the sky in a 24-hour period 
B) their apparent yearly cycle around the Sun,due to Earth's revolution 
C) their motion relative to all other bodies 
D) their motion relative to Earth 
A) their circular motion across the sky in a 24-hour period 
B) their apparent yearly cycle around the Sun,due to Earth's revolution 
C) their motion relative to all other bodies 
D) their motion relative to Earth

Question 6

A main sequence star begins transforming into a red giant when

Accepted Answer

A) helium begins fusing. 
B) helium within the core begins to expand. 
C) contracting helium causes hydrogen to fuse. 
D) hydrogen starts fusing within the core. 
A) helium begins fusing. 
B) helium within the core begins to expand. 
C) contracting helium causes hydrogen to fuse. 
D) hydrogen starts fusing within the core.

Question 7

It is theorized that a pulsar only emits X-rays and visible light during its early history.What do you suppose is the basis of this theory?

Accepted Answer

A) As the pulsar's energy dissipates,the frequency of the energy it emits drops. 
B) X-rays are likely the result of radioactive decay,which only can occur in a pulsar's early history. 
C) X-rays and visible light are both part of the electromagnetic spectrum. 
D) The pulsars high rate of spin produces a magnetic field that,over time,slows the pulsar down. 
A) As the pulsar's energy dissipates,the frequency of the energy it emits drops. 
B) X-rays are likely the result of radioactive decay,which only can occur in a pulsar's early history. 
C) X-rays and visible light are both part of the electromagnetic spectrum. 
D) The pulsars high rate of spin produces a magnetic field that,over time,slows the pulsar down.

Question 8

On the H-R diagram our Sun is a

Accepted Answer

A) white dwarf. 
B) star of average luminosity and temperature. 
C) red supergiant. 
D) relatively bright,blue star. 
A) white dwarf. 
B) star of average luminosity and temperature. 
C) red supergiant. 
D) relatively bright,blue star.

Question 9

The Milky Way galaxy is

Accepted Answer

A) in the process of colliding with the Magellanic Cloud galaxies. 
B) where Earth resides. 
C) a spiral galaxy. 
D) All of the above 
A) in the process of colliding with the Magellanic Cloud galaxies. 
B) where Earth resides. 
C) a spiral galaxy. 
D) All of the above

Question 10

If a star collapses to a tenth its size,gravitation at its surface increases by

Accepted Answer

A) ten. 
B) twenty. 
C) one hundred. 
D) one thousand. 
E) more than one thousand. 
A) ten. 
B) twenty. 
C) one hundred. 
D) one thousand. 
E) more than one thousand.

Question 11

Supernovae are one of the most extreme events in the known universe.They are caused by

Accepted Answer

A) the implosion of a white dwarf,which has run out of all its fuel. 
B) a supermassive supergiant star undergoing a massive nuclear chain reaction. 
C) the collapse of a supermassive supergiant star. 
D) Any of the above. 
A) the implosion of a white dwarf,which has run out of all its fuel. 
B) a supermassive supergiant star undergoing a massive nuclear chain reaction. 
C) the collapse of a supermassive supergiant star. 
D) Any of the above.

Question 12

Why can't any star,no matter how massive,fuse elements heavier than iron?

Accepted Answer

A) because the nucleons within iron have the least mass possible 
B) because elements heavier than iron have less average mass per nucleon 
C) It could happen,we just have not yet observed a star massive enough to do this. 
D) Actually,this occurs on a regular basis,which explains the great abundance of heavy elements. 
A) because the nucleons within iron have the least mass possible 
B) because elements heavier than iron have less average mass per nucleon 
C) It could happen,we just have not yet observed a star massive enough to do this. 
D) Actually,this occurs on a regular basis,which explains the great abundance of heavy elements.

Question 13

A light year is a unit of

Accepted Answer

A) time. 
B) energy. 
C) distance. 
D) mass. 
A) time. 
B) energy. 
C) distance. 
D) mass.

Question 14

How does the mass of a giant star compare with the mass of the black hole it may become? How do the densities compare?

Accepted Answer

The masses are the same! A black hole is

Question 15

The star nearest the Earth is

Accepted Answer

A) the Sun. 
B) Alpha Centauri. 
C) Polaris. 
D) the Moon. 
A) the Sun. 
B) Alpha Centauri. 
C) Polaris. 
D) the Moon.

Question 16

What are the outward forces that act on a star? What are the inward forces? How do these compare?

Accepted Answer

The outward forces on a star are radiati

Question 17

A pulsar is likely a

Accepted Answer

A) throbbing star in its death throes. 
B) black hole companion. 
C) spinning neutron star. 
D) binary star with a dark companion. 
A) throbbing star in its death throes. 
B) black hole companion. 
C) spinning neutron star. 
D) binary star with a dark companion.

Question 18

What event will eventually move an average star off the main sequence of the H-R diagram?

Accepted Answer

A) running out of hydrogen,causing gravitational influx,resulting in core temperatures high enough to begin fusing helium 
B) surface cooling due to hydrogen loss 
C) solar wind storms 
D) its drift through space due to the gravitational attraction of neighboring giant stars 
A) running out of hydrogen,causing gravitational influx,resulting in core temperatures high enough to begin fusing helium 
B) surface cooling due to hydrogen loss 
C) solar wind storms 
D) its drift through space due to the gravitational attraction of neighboring giant stars

Question 19

Why does a star's color corresponds to its temperature?

Accepted Answer

A) Higher temperature means more energetic light,which is seen as higher frequencies. 
B) Because of the light shifts that take place when star light interacts with the Earth's atmosphere 
C) Because the core temperature averages with the surface temperature to create an overall color 
D) Because the ultraviolet output of a star directly modifies the visible light spectrum the star is emitting 
A) Higher temperature means more energetic light,which is seen as higher frequencies. 
B) Because of the light shifts that take place when star light interacts with the Earth's atmosphere 
C) Because the core temperature averages with the surface temperature to create an overall color 
D) Because the ultraviolet output of a star directly modifies the visible light spectrum the star is emitting

Question 20

What determines if a star becomes a white dwarf,a neutron star,or a black hole?

Accepted Answer

A) the principal factor is mass 
B) the principal factor is density 
C) the principal factor is temperature 
D) the principal factor is luminosity 
A) the principal factor is mass 
B) the principal factor is density 
C) the principal factor is temperature 
D) the principal factor is luminosity

Exam 27: Stars and Galaxies

If the Sun collapsed to become a black hole,the Earth's gravitational attraction to it would be

Polaris is always directly overhead at

What will be the predominant element within the Sun after it has died?

A black hole has

Which best describes the intrinsic motion of stars?

A main sequence star begins transforming into a red giant when

It is theorized that a pulsar only emits X-rays and visible light during its early history.What do you suppose is the basis of this theory?

On the H-R diagram our Sun is a

The Milky Way galaxy is

If a star collapses to a tenth its size,gravitation at its surface increases by

Supernovae are one of the most extreme events in the known universe.They are caused by

Why can't any star,no matter how massive,fuse elements heavier than iron?

A light year is a unit of

How does the mass of a giant star compare with the mass of the black hole it may become? How do the densities compare?

The star nearest the Earth is

What are the outward forces that act on a star? What are the inward forces? How do these compare?

A pulsar is likely a

What event will eventually move an average star off the main sequence of the H-R diagram?

Why does a star's color corresponds to its temperature?

What determines if a star becomes a white dwarf,a neutron star,or a black hole?

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Momentum and Energy

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Magnetism and Electromagnetic Induction

Waves and Sound

Light

Atoms and the Periodic Table

The Atomic Nucleus and Radioactivity

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

How Chemicals React

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Time - Reading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

The Structure of Space and Time

Prologue: The Nature of Science

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