Question 1

After what evolutionary stage does a star become a white dwarf?

Accepted Answer

A)  Protostar 
B)  Pre-main sequence 
C)  Main sequence 
D)  Giant 
A)  Protostar 
B)  Pre-main sequence 
C)  Main sequence 
D)  Giant D

Question 2

Synchrotron radiation is produced

Accepted Answer

A)  in planetary nebulae. 
B)  by red dwarfs. 
C)  by massive stars as their iron core collapses. 
D)  in supernova remnants. 
E)  by neutrinos. 
A)  in planetary nebulae. 
B)  by red dwarfs. 
C)  by massive stars as their iron core collapses. 
D)  in supernova remnants. 
E)  by neutrinos. D

Question 3

Because massive stars have more gravitational energy than the sun,they can fuse heavier nuclear fuels.

Accepted Answer

A) True 
 B)False  True

Question 4

The explosion of a supernova typically leaves behind

Accepted Answer

A)  a planetary nebula. 
B)  a shell of hot,expanding gas with a white dwarf at the center. 
C)  a shell of hot,expanding gas with a pulsar at the center. 
D)  nothing is ever left behind. 
A)  a planetary nebula. 
B)  a shell of hot,expanding gas with a white dwarf at the center. 
C)  a shell of hot,expanding gas with a pulsar at the center. 
D)  nothing is ever left behind.

Question 5

A nova is almost always associated with

Accepted Answer

A)  a very massive star. 
B)  a very young star. 
C)  a star undergoing helium flash. 
D)  a white dwarf in a close binary system. 
E)  a solar like star that has exhausted its hydrogen and helium. 
A)  a very massive star. 
B)  a very young star. 
C)  a star undergoing helium flash. 
D)  a white dwarf in a close binary system. 
E)  a solar like star that has exhausted its hydrogen and helium.

Question 6

A type-II supernova

Accepted Answer

A)  occurs when a white dwarf's mass exceeds the Chandrasekhar limit. 
B)  is the result of helium flash. 
C)  is characterized by a spectrum that shows hydrogen lines. 
D)  occurs when the iron core of a massive star collapses. 
E)  c and d 
A)  occurs when a white dwarf's mass exceeds the Chandrasekhar limit. 
B)  is the result of helium flash. 
C)  is characterized by a spectrum that shows hydrogen lines. 
D)  occurs when the iron core of a massive star collapses. 
E)  c and d

Question 7

A white dwarf whose red giant companion dumps hydrogen onto it may

Accepted Answer

A)  show no effect. 
B)  explode recurrently as a nova. 
C)  blow up as a type I supernova. 
D)  answers b or 
A)  show no effect. 
B)  explode recurrently as a nova. 
C)  blow up as a type I supernova. 
D)  answers b or

Question 8

The Algol paradox is explained by considering

Accepted Answer

A)  the degenerate nature of the hydrogen on the surface of the white dwarf. 
B)  that iron is the most tightly bound of all atomic nuclei. 
C)  the rate of expansion of the shock wave inside the supernova. 
D)  the rotation rate of a neutron star. 
E)  mass transfer between the two stars in a binary system. 
A)  the degenerate nature of the hydrogen on the surface of the white dwarf. 
B)  that iron is the most tightly bound of all atomic nuclei. 
C)  the rate of expansion of the shock wave inside the supernova. 
D)  the rotation rate of a neutron star. 
E)  mass transfer between the two stars in a binary system.

Question 9

The diagram below shows a light curve from a supernova.How many days after maximum light did it take for the supernova to decrease in brightness by a factor of 100?

Accepted Answer

A)  25 
B)  50 
C)  100 
D)  150 
E)  250 
A)  25 
B)  50 
C)  100 
D)  150 
E)  250

Question 10

A planetary nebula

Accepted Answer

A)  produces an absorption spectrum. 
B)  produces an emission spectrum. 
C)  is contracting to form planets. 
D)  is contracting to form the star. 
E)  is the result of carbon detonation in a 1. 
A)  produces an absorption spectrum. 
B)  produces an emission spectrum. 
C)  is contracting to form planets. 
D)  is contracting to form the star. 
E)  is the result of carbon detonation in a 1.

Question 11

The Chandrasekhar limit is ____ solar masses.

Accepted Answer

A)  0.014 
B)  0.14 
C)  1.4 
D)  14 
A)  0.014 
B)  0.14 
C)  1.4 
D)  14

Question 12

A nova destroys the star and leaves behind a white dwarf.

Accepted Answer

A) True 
 B)False

Question 13

The energy a white dwarf emits into space is

Accepted Answer

A)  replaced by fusion of hydrogen atoms into helium. 
B)  replaced by fusion of helium atoms into carbon. 
C)  not replaced. 
A)  replaced by fusion of hydrogen atoms into helium. 
B)  replaced by fusion of helium atoms into carbon. 
C)  not replaced.

Question 14

Massive stars cannot generate energy through iron fusion because

Accepted Answer

A)  iron fusion requires very high density. 
B)  stars contain very little iron. 
C)  no star can get hot enough for iron fusion. 
D)  iron is the most tightly bound of all nuclei. 
E)  massive stars supernova before they create an iron core. 
A)  iron fusion requires very high density. 
B)  stars contain very little iron. 
C)  no star can get hot enough for iron fusion. 
D)  iron is the most tightly bound of all nuclei. 
E)  massive stars supernova before they create an iron core.

Question 15

The theory that the collapse of a massive star's iron core produces neutrinos was supported by

Accepted Answer

A)  the size and structure of the Crab nebula. 
B)  laboratory measurements of the mass of the neutrino. 
C)  calculation of models of core collapse. 
D)  underground counts from solar neutrinos. 
E)  the detection of neutrinos from the supernova of 1987. 
A)  the size and structure of the Crab nebula. 
B)  laboratory measurements of the mass of the neutrino. 
C)  calculation of models of core collapse. 
D)  underground counts from solar neutrinos. 
E)  the detection of neutrinos from the supernova of 1987.

Question 16

____________________ are caused by periodic eruptions in the helium fusion shell and may provide the energy to eject the material that forms a planetary nebula.

Accepted Answer

The answer of ____________________ are caused by periodic eruptions in...

Question 17

Where are elements heavier than iron primarily produced?

Accepted Answer

A)  Brown dwarfs 
B)  White dwarfs 
C)  Supergiants 
D)  Supernovae 
A)  Brown dwarfs 
B)  White dwarfs 
C)  Supergiants 
D)  Supernovae

Question 18

Electrons moving in a strong magnetic field emit ____________________ radiation.

Accepted Answer

The answer of Electrons moving in a strong magnetic field...

Question 19

A typical planetary nebula will be visible for about

Accepted Answer

A)  50 years. 
B)  500 years. 
C)  50,000 years. 
D)  5,000,000 years. 
E)  5 billion years. 
A)  50 years. 
B)  500 years. 
C)  50,000 years. 
D)  5,000,000 years. 
E)  5 billion years.

Question 20

For a star of Sun-like mass,what is the last stage of the nuclear fusion?

Accepted Answer

A)  Hydrogen to helium. 
B)  Helium to carbon and oxygen. 
C)  Carbon to magnesium. 
D)  Fusion goes all the way up to iron. 
A)  Hydrogen to helium. 
B)  Helium to carbon and oxygen. 
C)  Carbon to magnesium. 
D)  Fusion goes all the way up to iron.

Exam 13: The Deaths of Stars

After what evolutionary stage does a star become a white dwarf?

Synchrotron radiation is produced

Because massive stars have more gravitational energy than the sun,they can fuse heavier nuclear fuels.

The explosion of a supernova typically leaves behind

A nova is almost always associated with

A type-II supernova

A white dwarf whose red giant companion dumps hydrogen onto it may

The Algol paradox is explained by considering

The diagram below shows a light curve from a supernova.How many days after maximum light did it take for the supernova to decrease in brightness by a factor of 100?

A planetary nebula

The Chandrasekhar limit is ____ solar masses.

A nova destroys the star and leaves behind a white dwarf.

The energy a white dwarf emits into space is

Massive stars cannot generate energy through iron fusion because

The theory that the collapse of a massive star's iron core produces neutrinos was supported by

____________________ are caused by periodic eruptions in the helium fusion shell and may provide the energy to eject the material that forms a planetary nebula.

Where are elements heavier than iron primarily produced?

Electrons moving in a strong magnetic field emit ____________________ radiation.

A typical planetary nebula will be visible for about

For a star of Sun-like mass,what is the last stage of the nuclear fusion?

Here and Now

A Users Guide to the Sky

Cycles of the Moon

The Origin of Modern Astronomy

Gravity

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Interstellar Medium

The Formation and Structure of Stars

Stellar Evolution

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies

Active Galaxies and Supermassive Black Holes

Modern Cosmology

The Origin of the Solar System

Earth: the Standard of Comparative Planetology

The Moon and Mercury: Comparing Airless Worlds

Venus and Mars

Jupiter and Saturn

Uranus,neptune,and the Kuiper Belt

Meteorites,asteroids,and Comets

Astrobiology: Life on Other Worlds

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