Download PDF format

Chapter 18 Reading Quiz Clickers
The Cosmic Perspective
Seventh Edition
The Bizarre Stellar
Graveyard
© 2014 Pearson Education, Inc.
Chapter 18
18.1 White Dwarfs
• 
• 
What is a white dwarf?
What can happen to a white dwarf in a close binary
system?
© 2014 Pearson Education, Inc.
Chapter 18
What supports a white dwarf against the crush
of gravity?
a) 
b) 
c) 
d) 
thermal pressure
electron degeneracy pressure
neutron degeneracy pressure
proton degeneracy pressure
© 2014 Pearson Education, Inc.
Chapter 18
What supports a white dwarf against the crush
of gravity?
a) 
b) 
c) 
d) 
thermal pressure
electron degeneracy pressure
neutron degeneracy pressure
proton degeneracy pressure
© 2014 Pearson Education, Inc.
Chapter 18
What is the mass limit of a white dwarf?
a) 
b) 
c) 
d) 
e) 
0.8 solar masses
1.1 solar masses
1.4 solar masses
2.0 solar masses
8.0 solar masses
© 2014 Pearson Education, Inc.
Chapter 18
What is the mass limit of a white dwarf?
a) 
b) 
c) 
d) 
e) 
0.8 solar masses
1.1 solar masses
1.4 solar masses
2.0 solar masses
8.0 solar masses
© 2014 Pearson Education, Inc.
Chapter 18
How big is a white dwarf?
a) 
b) 
c) 
d) 
e) 
the size of a football field
the size of a city
the size of the Moon
the size of Earth
the size of Jupiter
© 2014 Pearson Education, Inc.
Chapter 18
How big is a white dwarf?
a) 
b) 
c) 
d) 
e) 
the size of a football field
the size of a city
the size of the Moon
the size of Earth
the size of Jupiter
© 2014 Pearson Education, Inc.
Chapter 18
What is a nova?
a)  the explosion of the core of a high mass star
b)  a burst of hydrogen fusion on the surface of a
white dwarf
c)  a burst of carbon fusion in a white dwarf
d)  a burst of helium fusion in a white dwarf
e)  radiation from a white dwarf accretion disk
© 2014 Pearson Education, Inc.
Chapter 18
What is a nova?
a)  the explosion of the core of a high mass star
b)  a burst of hydrogen fusion on the surface of a
white dwarf
c)  a burst of carbon fusion in a white dwarf
d)  a burst of helium fusion in a white dwarf
e)  radiation from a white dwarf accretion disk
© 2014 Pearson Education, Inc.
Chapter 18
What happens in a white dwarf supernova?
a) 
b) 
c) 
d) 
Carbon fuses throughout the white dwarf.
Hydrogen fuses on the surface of the white dwarf.
The white dwarf collapse into a neutron star.
Helium fuses throughout the white dwarf.
© 2014 Pearson Education, Inc.
Chapter 18
What happens in a white dwarf supernova?
a) 
b) 
c) 
d) 
Carbon fuses throughout the white dwarf.
Hydrogen fuses on the surface of the white dwarf.
The white dwarf collapse into a neutron star.
Helium fuses throughout the white dwarf.
© 2014 Pearson Education, Inc.
Chapter 18
18.2 Neutron Stars
• 
• 
• 
What is a neutron star?
How were neutron stars discovered?
What can happen to a neutron star in a close binary
system?
© 2014 Pearson Education, Inc.
Chapter 18
How big is a neutron star?
a) 
b) 
c) 
d) 
e) 
the size of a football field
the size of a city
the size of the Moon
the size of Earth
the size of Jupiter
© 2014 Pearson Education, Inc.
Chapter 18
How big is a neutron star?
a) 
b) 
c) 
d) 
e) 
the size of a football field
the size of a city
the size of the Moon
the size of Earth
the size of Jupiter
© 2014 Pearson Education, Inc.
Chapter 18
What is a pulsar?
a)  a high-mass star undergoing thermal pulses due to new shell
fusion layers in the interior
b)  a white dwarf in a binary system periodically going nova as it
accretes mass from the binary star
c)  a white dwarf in a binary system with a hot accretion spot
that periodically comes into view as the stars orbit each other
d)  a rotating neutron star beaming radiation along its magnetic
axis
© 2014 Pearson Education, Inc.
Chapter 18
What is a pulsar?
a)  a high-mass star undergoing thermal pulses due to new shell
fusion layers in the interior
b)  a white dwarf in a binary system periodically going nova as it
accretes mass from the binary star
c)  a white dwarf in a binary system with a hot accretion spot
that periodically comes into view as the stars orbit each other
d)  a rotating neutron star beaming radiation along its
magnetic axis
© 2014 Pearson Education, Inc.
Chapter 18
How do we know pulsars are neutron stars?
a)  The X-ray intensity is too strong to come from a white dwarf.
b)  Pulsars spin too fast to be as large as a white dwarf.
c)  The observed size of the accretion disk is too small to be a
white dwarf.
d)  The radiation shows a gravitational redshift that requires a
mass greater than the white dwarf limit.
© 2014 Pearson Education, Inc.
Chapter 18
How do we know pulsars are neutron stars?
a)  The X-ray intensity is too strong to come from a white dwarf.
b)  Pulsars spin too fast to be as large as a white dwarf.
c)  The observed size of the accretion disk is too small to be a
white dwarf.
d)  The radiation shows a gravitational redshift that requires a
mass greater than the white dwarf limit.
© 2014 Pearson Education, Inc.
Chapter 18
What produces X-ray bursts?
a)  radiation along the magnetic axis of a rapidly rotating
neutron star
b)  radiation from hydrogen fusion on the surface of a
neutron star in a binary system
c)  radiation from helium fusion on the surface of a neutron
star in a binary system
d)  the collapse of a white dwarf into a neutron star
e)  the collapse of a neutron star into a black hole
© 2014 Pearson Education, Inc.
Chapter 18
What produces X-ray bursts?
a)  radiation along the magnetic axis of a rapidly rotating
neutron star
b)  radiation from hydrogen fusion on the surface of a
neutron star in a binary system
c)  radiation from helium fusion on the surface of a
neutron star in a binary system
d)  the collapse of a white dwarf into a neutron star
e)  the collapse of a neutron star into a black hole
© 2014 Pearson Education, Inc.
Chapter 18
What is the maximum mass of a neutron star?
a) 
b) 
c) 
d) 
2-3 solar masses
5-7 solar masses
10 solar masses
26-30 solar masses
© 2014 Pearson Education, Inc.
Chapter 18
What is the maximum mass of a neutron star?
a) 
b) 
c) 
d) 
2-3 solar masses
5-7 solar masses
10 solar masses
26-30 solar masses
© 2014 Pearson Education, Inc.
Chapter 18
18.3 Black Holes: Gravity's Ultimate Victory
• 
• 
• 
What is a black hole?
What would it be like to visit a black hole?
Do black holes really exist?
© 2014 Pearson Education, Inc.
Chapter 18
What defines the event horizon?
a)  the physical surface of a black hole
b)  the boundary of the observable universe
c)  the distance from a black hole where the escape
velocity equals the speed of light
d)  the point at which the mass in a star's core cannot
be supported and collapses into a black hole
© 2014 Pearson Education, Inc.
Chapter 18
What defines the event horizon?
a)  the physical surface of a black hole
b)  the boundary of the observable universe
c)  the distance from a black hole where the escape
velocity equals the speed of light
d)  the point at which the mass in a star's core cannot
be supported and collapses into a black hole
© 2014 Pearson Education, Inc.
Chapter 18
Which of the following is not a property of a
black hole that can be known?
a) 
b) 
c) 
d) 
mass
temperature
charge
angular momentum
© 2014 Pearson Education, Inc.
Chapter 18
Which of the following is not a property of a
black hole that can be known?
a) 
b) 
c) 
d) 
mass
temperature
charge
angular momentum
© 2014 Pearson Education, Inc.
Chapter 18
What happens to time near a black hole?
a) 
b) 
c) 
d) 
e) 
It passes more slowly for stationary frames.
It passes more slowly for moving frames.
It passes more slowly for all frames.
It passes more quickly for moving frames.
It passes more quickly for all frames.
© 2014 Pearson Education, Inc.
Chapter 18
What happens to time near a black hole?
a) 
b) 
c) 
d) 
e) 
It passes more slowly for stationary frames.
It passes more slowly for moving frames.
It passes more slowly for all frames.
It passes more quickly for moving frames.
It passes more quickly for all frames.
© 2014 Pearson Education, Inc.
Chapter 18
How can we detect a black hole?
a)  Emission from a black hole accretion disk has a characteristic X-ray
spectrum.
b)  Observing a massive star supernova reveals the mass of the stellar
remnant, and if it exceeds 3 solar masses it must be a black hole.
c)  Observing the orbital motion of a star around a stellar remnant
reveals the mass of the stellar remnant, and if it exceeds 3 solar
masses it must be a black hole.
d)  Observation of an X-ray burst reveals the mass of the central object
through the gravitational redshift of the X-rays.
© 2014 Pearson Education, Inc.
Chapter 18
How can we detect a black hole?
a)  Emission from a black hole accretion disk has a characteristic X-ray
spectrum.
b)  Observing a massive star supernova reveals the mass of the stellar
remnant, and if it exceeds 3 solar masses it must be a black hole.
c)  Observing the orbital motion of a star around a stellar remnant
reveals the mass of the stellar remnant, and if it exceeds 3 solar
masses it must be a black hole.
d)  Observation of an X-ray burst reveals the mass of the central object
through the gravitational redshift of the X-rays.
© 2014 Pearson Education, Inc.
Chapter 18
18.4 The Origin of Gamma-Ray Bursts
• 
What causes gamma-ray bursts?
© 2014 Pearson Education, Inc.
Chapter 18
Where do gamma-ray bursts come from?
a) 
b) 
c) 
d) 
the disk of the Milky Way
the halo of the Milky Way
the center of the Milky Way
other galaxies
© 2014 Pearson Education, Inc.
Chapter 18
Where do gamma-ray bursts come from?
a) 
b) 
c) 
d) 
the disk of the Milky Way
the halo of the Milky Way
the center of the Milky Way
other galaxies
© 2014 Pearson Education, Inc.
Chapter 18
What is the cause of gamma-ray bursts?
a) 
b) 
c) 
d) 
e) 
massive star supernovae resulting in black holes
white dwarf supernovae
black hole mergers
all of the above
A and C
© 2014 Pearson Education, Inc.
Chapter 18
What is the cause of gamma-ray bursts?
a) 
b) 
c) 
d) 
e) 
massive star supernovae resulting in black holes
white dwarf supernovae
black hole mergers
all of the above
A and C
© 2014 Pearson Education, Inc.