Question 1

Of the various phases of matter,the one that is easiest to model and understand is

Accepted Answer

A)  solid. 
B)  liquid. 
C)  gas. 
D)  plasma. 
A)  solid. 
B)  liquid. 
C)  gas. 
D)  plasma.

Question 2

The dusty material being added to a protostar is known as a(n)

Accepted Answer

A)  dark nebula. 
B)  emission nebula. 
C)  planetary nebula. 
D)  circumstellar accretion disk. 
A)  dark nebula. 
B)  emission nebula. 
C)  planetary nebula. 
D)  circumstellar accretion disk.

Question 3

The stars that have the shortest lifetimes are

Accepted Answer

A)  K and M stars. 
B)  A and F stars 
C)  G and K stars. 
D)  O and B stars. 
A)  K and M stars. 
B)  A and F stars 
C)  G and K stars. 
D)  O and B stars.

Question 4

Describe the stellar evolution of a low-mass star over its entire life span.

Accepted Answer

Low-mass stars are formed from a large c

Question 5

Protostars with emission lines as well as absorption lines in their spectra and whose luminosity can change irregularly on time scales of a few days are called T Tauri stars.

Accepted Answer

A) True 
 B)False

Question 6

In what way could Population I stars be thought to be "recycled?"

Accepted Answer

Population I stars are second generation

Question 7

Some protostars,when they evolve onto the main sequence,are fully convective and use convection to transport material all the way from the core to the surface.Which stars show this characteristic?

Accepted Answer

A)  Only the smallest,with masses less than about 0.4 solar masses 
B)  Intermediate,with masses from about 0.4 solar masses up to about 4 solar masses 
C)  The largest,with masses above about 4 solar masses 
D)  All stars,regardless of solar mass 
A)  Only the smallest,with masses less than about 0.4 solar masses 
B)  Intermediate,with masses from about 0.4 solar masses up to about 4 solar masses 
C)  The largest,with masses above about 4 solar masses 
D)  All stars,regardless of solar mass

Question 8

Protostars are

Accepted Answer

A)  stars made almost entirely out of protons. 
B)  objects with masses less than about 0.08 solar masses,which do not have enough mass to become true stars. 
C)  old stars,contracting after using up all of their available hydrogen fuel. 
D)  very young objects,still contracting before becoming true stars. 
A)  stars made almost entirely out of protons. 
B)  objects with masses less than about 0.08 solar masses,which do not have enough mass to become true stars. 
C)  old stars,contracting after using up all of their available hydrogen fuel. 
D)  very young objects,still contracting before becoming true stars.

Question 9

Important information can be obtained from the H-R diagram of a star cluster because all stars in the cluster have approximately the same

Accepted Answer

A)  Doppler shift. 
B)  age. 
C)  spectral type. 
D)  luminosity class. 
A)  Doppler shift. 
B)  age. 
C)  spectral type. 
D)  luminosity class.

Question 10

The physical process believed to provide the energy for the ejection of a planetary nebula from a star is

Accepted Answer

A)  transfer of hydrogen-rich material to the surface of a white dwarf from its companion in a binary star system. 
B)  a series of thermal pulses in a helium-burning shell. 
C)  a collision with another star. 
D)  core collapse and the ensuing shock wave. 
A)  transfer of hydrogen-rich material to the surface of a white dwarf from its companion in a binary star system. 
B)  a series of thermal pulses in a helium-burning shell. 
C)  a collision with another star. 
D)  core collapse and the ensuing shock wave.

Question 11

How does the "turnoff point" on the H-R diagram determine the age of a cluster of stars?

Accepted Answer

More massive stars consume their fuel mo

Question 12

In terms of a star's evolutionary life,an asymptotic giant branch (AGB)star is in the

Accepted Answer

A)  helium-core-burning phase. 
B)  helium-shell-burning phase. 
C)  pre-main-sequence phase. 
D)  hydrogen-shell-burning phase prior to helium ignition in the core. 
A)  helium-core-burning phase. 
B)  helium-shell-burning phase. 
C)  pre-main-sequence phase. 
D)  hydrogen-shell-burning phase prior to helium ignition in the core.

Question 13

The triple-alpha process combines

Accepted Answer

A)  hydrogen atoms to form helium and release energy. 
B)  hydrogen atoms to form silicon and release energy. 
C)  helium atoms to form carbon and release energy. 
D)  oxygen atoms to form iron and release energy. 
A)  hydrogen atoms to form helium and release energy. 
B)  hydrogen atoms to form silicon and release energy. 
C)  helium atoms to form carbon and release energy. 
D)  oxygen atoms to form iron and release energy.

Question 14

When stars leave the main-sequence group,their core hydrogen is depleted and they become

Accepted Answer

A)  brighter and cooler. 
B)  brighter and hotter. 
C)  dimmer and cooler. 
D)  dimmer and hotter. 
A)  brighter and cooler. 
B)  brighter and hotter. 
C)  dimmer and cooler. 
D)  dimmer and hotter.

Question 15

How is the length of a star's lifetime related to the mass of the star?

Accepted Answer

A)  Higher-mass stars run through their lives faster and have shorter lifetimes. 
B)  The lifetimes of stars are too long to measure,so it is not known how their lifetimes depend on mass. 
C)  Lower-mass stars run through their lives faster and have shorter lifetimes. 
D)  A star's lifetime does not depend on its mass. 
A)  Higher-mass stars run through their lives faster and have shorter lifetimes. 
B)  The lifetimes of stars are too long to measure,so it is not known how their lifetimes depend on mass. 
C)  Lower-mass stars run through their lives faster and have shorter lifetimes. 
D)  A star's lifetime does not depend on its mass.

Question 16

Ultraviolet light from the exposed core of an average sized star at the end of its main-sequence life ionizes and excites the ejected gases,producing a

Accepted Answer

A)  planetary nebula. 
B)  supernova remnant. 
C)  corona. 
D)  photosphere. 
A)  planetary nebula. 
B)  supernova remnant. 
C)  corona. 
D)  photosphere.

Question 17

Which of the following would NOT be found in higher-than-average densities in an interstellar nebula?

Accepted Answer

A)  Electrons 
B)  Neutrinos 
C)  Dust 
D)  Protons 
A)  Electrons 
B)  Neutrinos 
C)  Dust 
D)  Protons

Question 18

Certain stages of stellar evolution,such as birth of a protostar and post-main-sequence red-giant evolution,come about because of an imbalance between gravity and

Accepted Answer

A)  high-energy neutrino pressure. 
B)  radiation intensity. 
C)  the centrifugal force from rotation. 
D)  internal gas pressure. 
A)  high-energy neutrino pressure. 
B)  radiation intensity. 
C)  the centrifugal force from rotation. 
D)  internal gas pressure.

Question 19

In astronomical terms,planetary nebulae

Accepted Answer

A)  exist around their central white dwarf stars for millions of years before slowly spreading into space. 
B)  are relatively long-lived because they form when the original stars form and remain as slowly rotating shells for the whole of the star's lifetime of several billion years. 
C)  are very short-lived,with lifetimes of about 50,000 years. 
D)  are very long-lived objects,having been in existence since the Big Bang at the beginning of the universe. 
A)  exist around their central white dwarf stars for millions of years before slowly spreading into space. 
B)  are relatively long-lived because they form when the original stars form and remain as slowly rotating shells for the whole of the star's lifetime of several billion years. 
C)  are very short-lived,with lifetimes of about 50,000 years. 
D)  are very long-lived objects,having been in existence since the Big Bang at the beginning of the universe.

Question 20

What kind of star is our Sun?

Accepted Answer

A)  Metal-poor Population I 
B)  Metal-rich Population I 
C)  Metal-poor Population II 
D)  None of these 
A)  Metal-poor Population I 
B)  Metal-rich Population I 
C)  Metal-poor Population II 
D)  None of these

Of the various phases of matter,the one that is easiest to model and understand is

The dusty material being added to a protostar is known as a(n)

The stars that have the shortest lifetimes are

Describe the stellar evolution of a low-mass star over its entire life span.

Protostars with emission lines as well as absorption lines in their spectra and whose luminosity can change irregularly on time scales of a few days are called T Tauri stars.

In what way could Population I stars be thought to be "recycled?"

Some protostars,when they evolve onto the main sequence,are fully convective and use convection to transport material all the way from the core to the surface.Which stars show this characteristic?

Protostars are

Important information can be obtained from the H-R diagram of a star cluster because all stars in the cluster have approximately the same

The physical process believed to provide the energy for the ejection of a planetary nebula from a star is

How does the "turnoff point" on the H-R diagram determine the age of a cluster of stars?

In terms of a star's evolutionary life,an asymptotic giant branch (AGB)star is in the

The triple-alpha process combines

When stars leave the main-sequence group,their core hydrogen is depleted and they become

How is the length of a star's lifetime related to the mass of the star?

Ultraviolet light from the exposed core of an average sized star at the end of its main-sequence life ionizes and excites the ejected gases,producing a

Which of the following would NOT be found in higher-than-average densities in an interstellar nebula?

Certain stages of stellar evolution,such as birth of a protostar and post-main-sequence red-giant evolution,come about because of an imbalance between gravity and

In astronomical terms,planetary nebulae

What kind of star is our Sun?

Predicting the Motions of the Stars, Sun, and Moon

Decoding the Hidden Messages in Starlight

Analyzing Scales and Motions of the Universe

Exploring Our Evolving Solar System

Uncovering Earths Systems

Exploring Terrestrial Surface Processes and Atmospheres

Observing the Dynamic Giant Planets

Looking for Life Beyond Earth

Probing the Dynamic Sun

Observing Properties of Distant Stars

Predicting the Violent End of the Largest Stars

Exploring Our Galaxy

Investigating Other Galaxies

Observing the Evolution of the Universe

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Exam 11: Inferring Patterns in Star Life Cycles

Of the various phases of matter,the one that is easiest to model and understand is

The dusty material being added to a protostar is known as a(n)

The stars that have the shortest lifetimes are

Describe the stellar evolution of a low-mass star over its entire life span.

Protostars with emission lines as well as absorption lines in their spectra and whose luminosity can change irregularly on time scales of a few days are called T Tauri stars.

In what way could Population I stars be thought to be "recycled?"

Some protostars,when they evolve onto the main sequence,are fully convective and use convection to transport material all the way from the core to the surface.Which stars show this characteristic?

Protostars are

Important information can be obtained from the H-R diagram of a star cluster because all stars in the cluster have approximately the same

The physical process believed to provide the energy for the ejection of a planetary nebula from a star is

How does the "turnoff point" on the H-R diagram determine the age of a cluster of stars?

In terms of a star's evolutionary life,an asymptotic giant branch (AGB)star is in the

The triple-alpha process combines

When stars leave the main-sequence group,their core hydrogen is depleted and they become

How is the length of a star's lifetime related to the mass of the star?

Ultraviolet light from the exposed core of an average sized star at the end of its main-sequence life ionizes and excites the ejected gases,producing a

Which of the following would NOT be found in higher-than-average densities in an interstellar nebula?

Certain stages of stellar evolution,such as birth of a protostar and post-main-sequence red-giant evolution,come about because of an imbalance between gravity and

In astronomical terms,planetary nebulae

What kind of star is our Sun?

Predicting the Motions of the Stars, Sun, and Moon

Decoding the Hidden Messages in Starlight

Analyzing Scales and Motions of the Universe

Exploring Our Evolving Solar System

Uncovering Earths Systems

Exploring Terrestrial Surface Processes and Atmospheres

Observing the Dynamic Giant Planets

Looking for Life Beyond Earth

Probing the Dynamic Sun

Observing Properties of Distant Stars

Predicting the Violent End of the Largest Stars

Exploring Our Galaxy

Investigating Other Galaxies

Observing the Evolution of the Universe

Filters