Download Test 4 Review Clicker Questions

Test 4 Review
Clicker Question
Chs 13,14,15,16,&17
Copyright © 2010 Pearson Education, Inc.
Question 13-1
One possible
explanation for a
gamma-ray
burster is
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a) matter spiraling into a large black
hole.
b) the collision of neutron stars in a
binary system.
c) variations in the magnetic fields of
a pulsar.
d) repeated nova explosions.
e) All of the above are possible.
Question 13-1
One possible
explanation for a
gamma-ray
burster is
a) matter spiraling into a large black
hole.
b) the collision of neutron stars in a
binary system.
c) variations in the magnetic fields of
a pulsar.
d) repeated nova explosions.
e) All of the above are possible.
Gamma-ray bursts vary in
length, and the coalescence of
two neutron stars seems to
account for short bursts.
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Question 13-2
Cygnus X-1 is
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a) NASA’s latest X-ray orbiting telescope.
b) a millisecond pulsar with three planets.
c) the strongest X-ray eclipsing binary system.
d) a likely black hole binary star system.
e) the first gamma-ray burster spotted in X rays.
Question 13-2
Cygnus X-1 is
a) NASA’s latest X-ray orbiting telescope.
b) a millisecond pulsar with three planets.
c) the strongest X-ray eclipsing binary system.
d) a likely black hole binary star system.
e) the first gamma-ray burster spotted in X rays.
Cygnus X-1 is an X-ray source with
one visible star orbited by an unseen
companion of at least 10 solar
masses, and very rapid changes in the
signal indicating a small source.
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Question 13-3
The force of gravity
can pull on
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a) a beam of light.
b) a massive object.
c) neutrinos.
d) antimatter.
e) All of the above are correct.
Question 13-3
The force of gravity
can pull on
a) a beam of light.
b) a massive object.
c) neutrinos.
d) antimatter.
e) All of the above are correct.
Gravity is described by
general relativity as a
bending of space, and all
particles, including photons,
move through warped space
along curved paths.
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Question 13-4
If the sun was
replaced by a
one-solar-mass
black hole
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a) Earth’s orbit would not change.
b) Earth would be pulled into the
black hole.
c) X rays would destroy Earth.
d) Earth would be torn apart from the
tidal force.
e) life would be unchanged.
Question 13-4
If the sun was
replaced by a
one-solar-mass
black hole
a) Earth’s orbit would not change.
b) Earth would be pulled into the
black hole.
c) X rays would destroy Earth.
d) Earth would be torn apart from the
tidal force.
e) life would be unchanged.
The force of gravity depends only on mass and
distance, not the type of matter, or its size.
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Question 13-5
The event horizon
of a black hole
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a) is the point where X rays emerge.
b) is the physical surface of the hole.
c) defines the outer edge of an accretion
disk.
d) is measured by the Schwarzschild
radius.
e) extends for millions of miles into
space.
Question 13-5
The event horizon
of a black hole
a) is the point where X rays emerge.
b) is the physical surface of the hole.
c) defines the outer edge of an accretion
disk.
d) is measured by the Schwarzschild
radius.
e) extends for millions of miles into
space.
The event horizon is the surface of an
imaginary sphere around a collapsed
object inside of which nothing,
including light, can escape.
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Question 14-1
The location of the
galactic center was
identified using
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a) supernova remnants.
b) white dwarf stars in the spiral arms.
c) red giant variable stars in globular
clusters.
d) bright O and B stars in open clusters.
e) X-ray sources.
Question 14-1
The location of the
galactic center was
identified using
a) supernova remnants.
b) white dwarf stars in the spiral arms.
c) red giant variable stars in globular
clusters.
d) bright O and B stars in open clusters.
e) X-ray sources.
Harlow Shapley used pulsating RRLyrae variables as distance indicators
to the globular clusters.
He then deduced the distance and
direction of the Milky Way’s center.
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Question 14-2
Our Sun is
located in the
Milky Way
Galaxy
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a) about 30 Kpc from the center in the
halo.
b) 30,000 light-years from the center in
a globular cluster.
c) at the outer edge of the galactic disk,
in the plane.
d) about halfway from the center, in the
spiral arms.
e) in the bulge, near the Orion arm.
Question 14-2
Our Sun is
located in the
Milky Way
Galaxy
a) about 30 Kpc from the center in the
halo.
b) 30,000 light-years from the center in
a globular cluster.
c) at the outer edge of the galactic disk,
in the plane.
d) about halfway from the center, in the
spiral arms.
e) in the bulge, near the Orion arm.
The Sun orbits the center of
the Galaxy within the disk,
taking about 225 million years
to complete one orbit.
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Question 14-3
The period –
luminosity
relationship is
a crucial
component of
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a) measuring distances with Cepheid
variable stars.
b) identifying the mass of the Galaxy’s
central black hole.
c) determining the masses of stars in
an eclipsing binary system.
d) using spectroscopic parallax to
measure distances to stars.
Question 14-3
The period –
luminosity
relationship is
a crucial
component of
a) measuring distances with Cepheid
variable stars.
b) identifying the mass of the Galaxy’s
central black hole.
c) determining the masses of stars in
an eclipsing binary system.
d) using spectroscopic parallax to
measure distances to stars.
Cepheid variable stars with
longer periods have higher
actual luminosities; short-period
Cepheids are dimmer.
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Question 14 - 4
High-speed motion
of gas and stars
near the Milky Way
Galaxy’s center is
explained by
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a) tidal forces from the Andromeda Galaxy.
b) accretion disks around neutron stars.
c) gamma-ray bursts.
d) gravitation from globular clusters.
e) a supermassive black hole.
Question 14 - 4
High-speed motion
of gas and stars
near the Milky Way
Galaxy’s center is
explained by
a) tidal forces from the Andromeda Galaxy.
b) accretion disks around neutron stars.
c) gamma-ray bursts.
d) gravitation from globular clusters.
e) a supermassive black hole.
Recent observations
estimate the black hole to be
4 million solar masses.
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Question 14 - 5
Detailed measurements
of the disk suggest that
our Milky Way is
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a) a spiral galaxy.
b) a barred spiral galaxy.
c) an elliptical galaxy.
d) a quasar.
e) an irregular galaxy.
Question 14 - 5
Detailed measurements
of the disk suggest that
our Milky Way is
a) a spiral galaxy.
b) a barred spiral galaxy.
c) an elliptical galaxy.
d) a quasar.
e) an irregular galaxy.
Measurements of stellar motion in and near the bulge
imply that it is football shaped, about half as wide as it is
long, characteristic of a barred spiral galaxy.
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Question 14 - 6
What two
observations
allow us to
estimate the
Galaxy’s mass?
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a) the Sun’s mass and velocity in orbit
around the galactic center
b) the rotation of the bulge and disk
components
c) the Sun’s age and age of globular
cluster stars
d) the motion of spiral arms and the
mass of the central black hole
e) the Sun’s orbital period and distance
from the center
Question 14 - 6
What two
observations
allow us to
estimate the
Galaxy’s mass?
a) the Sun’s mass and velocity in orbit
around the galactic center
b) the rotation of the bulge and disk
components
c) the Sun’s age and age of the globular
cluster stars
d) the motion of spiral arms and mass
of the central black hole
e) the Sun’s orbital period and distance
from the center
Use the modified form of Kepler’s law to find the mass:
Total mass = (orbital size)3 / (orbital period)2
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Question 14 - 7
In the formation
of our Galaxy
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a) the spiral arms formed first.
b) the globular clusters formed first.
c) the disk component started out thin
and grew.
d) spiral density waves formed first.
e) the bar in the bulge formed first.
Question 14 - 7
In the formation
of our Galaxy
a) the spiral arms formed first.
b) the globular clusters formed first.
c) the disk component started out thin
and grew.
d) spiral density waves formed first.
e) the bar in the bulge formed first.
Globular clusters contain
very old stars, no gas or
dust, and orbit around the
center randomly.
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Question 14 - 8
21-cm radio
radiation is useful
in studying our
Galaxy because
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a) the waves penetrate dusty cocoons
to reveal star formation.
b) it reflects from the Galaxy’s core.
c) the waves are not absorbed by
galactic black holes.
d) it can be used to map out the cool
hydrogen in spiral arms.
e) radio waves provide a distance
measurement like parallax.
Question 14 - 8
21-cm radio
radiation is useful
in studying our
Galaxy because
a) the waves penetrate dusty cocoons
to reveal star formation.
b) it reflects from the Galaxy’s core.
c) the waves are not absorbed by
galactic black holes.
d) it can be used to map out the cool
hydrogen in spiral arms.
e) radio waves provide a distance
measurement like parallax.
The Doppler shifts of 21-cm radiation from
hydrogen in the spiral arms provides
astronomers with a tool to map out the
Galaxy’s structure.
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Question 14 - 9
Which of these
is not a typical
part of our
Galaxy’s spiral
arms?
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a) OB associations
b) open clusters
c) giant molecular clouds
d) emission nebulae
e) Population II red giant stars
Question 14 - 9
Which of these
is not a typical
part of our
Galaxy’s spiral
arms?
a) OB associations
b) open clusters
c) giant molecular clouds
d) emission nebulae
e) Population II red giant stars
The spiral arms contain gas,
dust, molecular clouds, new
clusters, and Population I stars.
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Question 14 - 10
What suggests that
the mass of our
Galaxy extends
farther than its
visible disk?
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a) 21-cm maps of the spiral arms
b) the rotation curve of the outer edges
of the Galaxy
c) orbits of open clusters in the disk
d) infrared observations of new starforming regions
e) X-ray images of other galaxies
Question 14 - 10
What suggests that
the mass of our
Galaxy extends
farther than its
visible disk?
a) 21-cm maps of the spiral arms
b) the rotation curve of the outer edges
of the Galaxy
c) orbits of open clusters in the disk
d) infrared observations of new starforming regions
e) X-ray images of other galaxies
The outer edges of the
Galaxy’s disk rotate much
faster than they should.
Most of the mass of the
Galaxy must be dark matter.
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Question 15 - 1
Based on their
shapes and stars,
elliptical galaxies
are most like the
Milky Way’s
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a) disk and spiral arms.
b) halo.
c) central bulge.
d) open clusters.
e) companion galaxies, the Magellanic
Clouds.
Question 15 - 1
Based on their
shapes and stars,
elliptical galaxies
are most like the
Milky Way’s
a) disk and spiral arms.
b) halo.
c) central bulge.
d) open clusters.
e) companion galaxies, the Magellanic
Clouds.
Like the stars and globular
clusters in our halo, elliptical
galaxies contain little or no gas
and dust to make new stars.
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Question 15 - 2
What property is
shared by spiral
galaxies?
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a) ongoing star formation
b) a disk, bulge, and halo
c) globular clusters in the halo
d) open clusters in the disk
e) all of the above
Question 15 - 2
What property is
shared by spiral
galaxies?
a) ongoing star formation
b) a disk, bulge, and halo
c) globular clusters in the halo
d) open clusters in the disk
e) all of the above
M-51, a Type Sb spiral
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Question 15 - 3
The Magellanic
Clouds are
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a) giant globular clusters in the halo.
b) small irregular galaxies that orbit the
Milky Way.
c) large molecular clouds in the disk of
our Galaxy.
d) the brightest ionized hydrogen
regions in our Galaxy.
e) spiral nebulae originally discovered
by Herschel.
Question 15 - 3
The Magellanic
Clouds are
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a) giant globular clusters in the halo.
b) small irregular galaxies that orbit the
Milky Way.
c) large molecular clouds in the disk of
our Galaxy.
d) the brightest ionized hydrogen
regions in our Galaxy.
e) spiral nebulae originally discovered
by Herschel.
Question 15 - 4
Hubble took
spectra of
galaxies in the
1930s. What did
he find?
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a) Most galaxies showed redshifts.
b) All galaxies showed blueshifts.
c) Galaxies showed about half redshifts and
half blueshifts.
d) Galaxies showed no line shifts at all.
e) Some galaxies showed a redshift that
changed into a blueshift at other times.
Question 15 - 4
Hubble took
spectra of
galaxies in the
1930s. What did
he find?
a) Most galaxies showed redshifts.
b) All galaxies showed blueshifts.
c) Galaxies showed about half redshifts and
half blueshifts.
d) Galaxies showed no line shifts at all.
e) Some galaxies showed a redshift that
changed into a blueshift at other times.
Redshifts of
galaxies indicate
they are moving
away from us.
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Question 15 - 5
Hubble’s law is
based on
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a) more distant galaxies showing greater
blueshifts.
b) distant quasars appearing proportionally
dimmer.
c) more distant galaxies showing greater
redshifts.
d) slowly varying Cepheid variables
appearing brighter.
e) more distant galaxies appearing younger.
Question 15 - 5
Hubble’s law is
based on
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a) more distant galaxies showing greater
blueshifts.
b) distant quasars appearing proportionally
dimmer.
c) more distant galaxies showing greater
redshifts.
d) slowly varying Cepheid variables
appearing brighter.
e) more distant galaxies appearing younger.
Question 15 - 6
Hubble’s constant
measures
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a) the density of galaxies in the universe.
b) the luminosity of distant galaxies.
c) the reddening of light from dust clouds.
d) the speed of a galaxy.
e) the rate of expansion of the universe.
Question 15 - 6
Hubble’s constant
measures
Velocity = H0 x Distance
a) the density of galaxies in the universe.
b) the luminosity of distant galaxies.
c) the reddening of light from dust clouds.
d) the speed of a galaxy.
e) the rate of expansion of the universe.
Hubble’s law relates how fast
galaxies are moving away from us
at different distances.
A larger value for H0 implies a faster
expansion rate.
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Question 15 - 7
To calibrate
Hubble’s constant,
astronomers must
determine
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a) the size of the universe.
b) distances to galaxies.
c) the speed of recession of galaxies.
d) the density of matter in the universe.
e) the temperature of the Big Bang.
Question 15 - 7
To calibrate
Hubble’s constant,
astronomers must
determine
a) the size of the universe.
b) distances to galaxies.
c) the speed of recession of galaxies.
d) the density of matter in the universe.
e) the temperature of the Big Bang.
Distances to galaxies are determined
using a variety of “standard candles,”
including Cepheid variables,
supernova explosions, model galaxies,
and model clusters.
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Question 15 - 8
Hubble’s
discovery of
galaxy redshifts
means
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a) the universe is static.
b) the universe is collapsing.
c) the universe is expanding.
d) the Milky Way is the center of the
universe.
e) There is no accepted interpretation.
Question 15 - 8
Hubble’s
discovery of
galaxy redshifts
means
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a) the universe is static.
b) the universe is collapsing.
c) the universe is expanding.
d) the Milky Way is the center of the
universe.
e) There is no accepted interpretation.
Question 15 - 9
Quasars are
“quasi-stellar”
because
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a) they generate energy partly through H to
He fusion like stars.
b) they show spectra similar to extremely
bright O stars.
c) their luminosity varies like eclipsing
binary stars.
d) in short exposure photographs, their
images appear stellar.
e) they are dense concentrations of millions
of stars.
Question 15 - 9
Quasars are
“quasi-stellar”
because
a) they generate energy partly through H to
He fusion like stars.
b) they show spectra similar to extremely
bright O stars.
c) their luminosity varies like eclipsing
binary stars.
d) in short exposure photographs, their
images appear stellar.
e) they are dense concentrations of millions
of stars.
Although short-exposure images
can appear starlike, many
quasars show jets or other signs
of intense activity.
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Question 15 - 10
Seyfert and radio
galaxies could be
powered by
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a) supermassive black holes at their
cores.
b) dark matter.
c) self-sustaining star formation.
d) spiral density waves.
e) hypernova explosions.
Question 15 - 10
Seyfert and radio
galaxies could be
powered by
a) supermassive black holes at their
cores.
b) dark matter.
c) self-sustaining star formation.
d) spiral density waves.
e) hypernova explosions.
The Circinus
Galaxy, a Seyfert
galaxy about 4
Mpc away
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Question 15 - 11
In active galaxies,
the central engine
can be “fed” by
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a) sudden bursts of star formation.
b) supernova chain reactions in the core.
c) the collapse of the core into a larger black
hole.
d) close encounters with a nearby galaxy.
e) dark matter becoming visible and
emitting light.
Question 15 - 11
In active galaxies,
the central engine
can be “fed” by
a) sudden bursts of star formation.
b) supernova chain reactions in the core.
c) the collapse of the core into a larger black
hole.
d) close encounters with a nearby galaxy.
e) dark matter becoming visible and
emitting light.
Collisions or tidal interaction between
galaxies can provide new fuel to power
the supermassive black hole engines of
active galaxies.
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Question 16 - 1
Based on galactic
rotation curves and
motions in clusters
of galaxies, dark
matter
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a) makes up about 90 percent of the
matter in the universe.
b) is best detected by the largest optical
telescopes.
c) makes up about 10 percent of the
matter in clusters of galaxies.
d) exists but has no observable effects
on galaxies.
e) is the result of gas and dust.
Question 16 - 1
Based on galactic
rotation curves and
motions in clusters
of galaxies, dark
matter
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a) makes up about 90 percent of the
matter in the universe.
b) is best detected by the largest optical
telescopes.
c) makes up about 10 percent of the
matter in clusters of galaxies.
d) exists but has no observable effects
on galaxies.
e) is the result of gas and dust.
Question 16 - 2
Collisions
between galaxies
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a) are much rarer than collisions between
stars.
b) can transform elliptical galaxies into
spirals.
c) trigger Type II supernova explosions in
the halo.
d) cause gas and dust clouds to collide,
leading to rapid star formation.
Question 16 - 2
Collisions
between galaxies
a) are much rarer than collisions between
stars.
b) can transform elliptical galaxies into
spirals.
c) trigger Type II supernova explosions in
the halo.
d) cause gas and dust clouds to collide,
leading to rapid star formation.
Galaxies are relatively
close compared with
their size. In clusters of
galaxies, collisions
clearly occur.
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Question 16 - 3
When spiral galaxies
collide, the greatest
impact occurs on
their
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a) globular cluster stars.
b) giant molecular clouds.
c) central bulge stars.
d) open clusters.
e) disk stars.
Question 16 - 3
When spiral galaxies
collide, the greatest
impact occurs on
their
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a) globular cluster stars.
b) giant molecular clouds.
c) central bulge stars.
d) open clusters.
e) disk stars.
Question 16 - 4
Due to the density and
collisions among galaxies,
___________ are rare in the
centers of clusters.
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a) giant ellipticals
b) irregulars
c) spirals
d) active galaxies
e) radio galaxies
Question 16 - 4
Due to the density and
collisions among galaxies,
___________ are rare in the
centers of clusters.
a) giant ellipticals
b) irregulars
c) spirals
d) active galaxies
e) radio galaxies
The gas, dust, and disks of spiral
galaxies are tidally disrupted, and
even destroyed, in the centers of
dense clusters, which are often
dominated by giant elliptical galaxies.
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Question 16 - 5
The rapid variation
of brightness of
quasars indicates
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a) the source of energy is very small.
b) energy is coming from matter and
antimatter.
c) the energy source is rotating rapidly.
d) a chain reaction of supernovas occurs.
e) there are many separate sources of
energy in the core.
Question 16 - 5
The rapid variation
of brightness of
quasars indicates
a) the source of energy is very small.
b) energy is coming from matter and
antimatter.
c) the energy source is rotating rapidly.
d) a chain reaction of supernovas occurs.
e) there are many separate sources of
energy in the core.
The size of an object
cannot be larger than the
distance light can travel
in the time it takes to
change its brightness.
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Question 16 - 6
A galaxy seen
1 billion
light-years
away means
we see it
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a) as it was when the universe was 1 billion
years old.
b) as it will be 1 billion years from now.
c) as it was 1 billion years ago.
d) as it is today, but redshifted 10 percent of
the speed of light.
e) as it was just after the Big Bang.
Question 16 - 6
A galaxy seen
1 billion
light-years
away means
we see it
a) as it was when the universe was 1 billion
years old.
b) as it will be 1 billion years from now.
c) as it was 1 billion years ago.
d) as it is today, but redshifted 10 percent of
the speed of light.
e) as it was just after the Big Bang.
Looking farther away in
space means looking
back further in time, to
when the object (and
universe) was younger.
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Question 16 - 7
The large-scale
distribution of
galaxies in the
universe reveals
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a) a smooth, continuous, and homogeneous
arrangement of clusters.
b) large voids, with most of the galaxies
lying in filaments and sheets.
c) a large supercluster at the center of the
universe.
d) a central void with walls of galaxies at the
edge of the universe.
Question 16 - 7
The large-scale
distribution of
galaxies in the
universe reveals
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a) a smooth, continuous, and homogeneous
arrangement of clusters.
b) large voids, with most of the galaxies
lying in filaments and sheets.
c) a large supercluster at the center of the
universe.
d) a central void with walls of galaxies at the
edge of the universe.
Question 16 - 8
The lensing of a
distant quasar
is produced in a
foreground
galaxy by its
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a) total mass of stars, gas, and dark
matter.
b) central supermassive black hole.
c) globular clusters.
d) magnetic fields.
e) intergalactic gas.
Question 16 - 8
The lensing of a
distant quasar
is produced in a
foreground
galaxy by its
a) total mass of stars, gas, and dark
matter.
b) central supermassive black hole.
c) globular clusters.
d) magnetic fields.
e) intergalactic gas.
The twin quasar AC114
has two images of the
same object.
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Question 17 - 1
Because distant
galaxies in every
direction are
moving away
from us,
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a) the Milky Way must be located at the
edge of the universe.
b) the Milky Way is at the center of the
universe.
c) the universe is expanding.
d) the sky is dark at night.
e) the universe has not changed
significantly.
Question 17 - 1
Because distant
galaxies in every
direction are
moving away
from us,
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a) the Milky Way must be located at the
edge of the universe.
b) the Milky Way is at the center of the
universe.
c) the universe is expanding.
d) the sky is dark at night.
e) the universe has not changed
significantly.
Question 17 - 2
Hubble’s
constant, H0, can
be related to
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a) the size of the universe.
b) the age of the universe.
c) the shape of the universe.
d) the temperature of the universe.
e) the distance the universe has
expanded.
Question 17 - 2
Hubble’s
constant, H0, can
be related to
a) the size of the universe.
b) the age of the universe.
c) the shape of the universe.
d) the temperature of the universe.
e) the distance the universe has
expanded.
H0 is currently
estimated to be about
70 km/sec/Mpc.
This translates to an
age for the universe of
about 14 billion years.
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Question 17 - 3
The redshift of
galaxies is
explained best as
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a) a Doppler shift of the random motions of
galaxies.
b) an aging of light as the universe ages.
c) space itself expanding with time,
stretching light.
d) the result of the Milky Way’s position at
the center.
e) due to the temperature differences in the
early and late universe.
Question 17 - 3
The redshift of
galaxies is
explained best as
a) a Doppler shift of the random motions of
galaxies.
b) an aging of light as the universe ages.
c) space itself expanding with time,
stretching light.
d) the result of the Milky Way’s position at
the center.
e) due to the temperature differences in the
early and late universe.
As the universe
expands, photons
of radiation are
stretched in
wavelength as
they move
through space.
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Question 17 - 4
Hubble’s law
implies that the
universe
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a) is infinitely old and getting larger.
b) began expanding long ago, and has a
finite age.
c) will slow down because of dark matter.
d) has repeatedly expanded and
contracted.
e) will eventually stop and recollapse.
Question 17 - 4
Hubble’s law
implies that the
universe
a) is infinitely old and getting larger.
b) began expanding long ago, and has a
finite age.
c) will slow down because of dark matter.
d) has repeatedly expanded and
contracted.
e) will eventually stop and recollapse.
Using the Hubble
constant H0,
astronomers can
estimate that the
universe was born
about 14 billion
years ago.
Copyright © 2010 Pearson Education, Inc.
Question 17 - 5
The cosmic
microwave
background
radiation is
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a) evidence supporting the Big Bang.
b) proof that the universe is getting warmer.
c) a result of the hot intergalactic gas between
clusters.
d) the observable form of dark energy.
e) released from the first generation of stars in
the universe.
Question 17 - 5
The cosmic
microwave
background
radiation is
a) evidence supporting the Big Bang.
b) proof that the universe is getting warmer.
c) a result of the hot intergalactic gas between
clusters.
d) the observable form of dark energy.
e) released from the first generation of stars in
the universe.
The radiation observed is
the “fossil remnant” of the
primeval fireball that
existed at the very
beginning of the universe.
Copyright © 2010 Pearson Education, Inc.
Question 17 - 6
The darkness of
the sky in an
infinite universe
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a) is explained by general relativity.
b) results from the presence of dark matter.
c) is a statement of Olbers’ paradox.
d) is the cosmological principle.
e) occurs if the universe is static and
unchanging.
Question 17 - 6
The darkness of
the sky in an
infinite universe
a) is explained by general relativity.
b) results from the presence of dark matter.
c) is a statement of Olbers’ paradox.
d) is the cosmological principle.
e) occurs if the universe is static and
unchanging.
If the universe is homogeneous
in composition, and appears the
same in all directions, then for
the sky to be dark, it must be
either finite in age, or evolving in
time, or both.
Copyright © 2010 Pearson Education, Inc.
Question 17 - 7
In a closed
universe
Copyright © 2010 Pearson Education, Inc.
a) the universe will eventually stop expanding and
recollapse.
b) dark matter will dominate over dark energy.
c) the universe will stop expanding and remain
stationary.
d) dark energy will dominate over dark matter.
e) the universe will not stop expanding.
Question 17 - 7
In a closed
universe
a) the universe will eventually stop expanding and
recollapse.
b) dark matter will dominate over dark energy.
c) the universe will stop expanding and remain
stationary.
d) dark energy will dominate over dark matter.
e) the universe will not stop expanding.
Greater density means
more matter in a smaller
volume, and gravity will be
strong enough to stop the
expansion and cause a
“Big Crunch.”
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Question 17 - 8
If the density
of the
universe is
greater than
“critical”,
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a) there is more matter than energy.
b) the universe is closed, and will recollapse.
c) the universe is open, and will keep
expanding.
d) dark matter will dominate, and galaxies will
stop expanding.
e) there was more helium than hydrogen
created in the Big Bang.
Question 17 - 8
If the density
of the
universe is
greater than
“critical”,
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a) there is more matter than energy.
b) the universe is closed, and will recollapse.
c) the universe is open, and will keep
expanding.
d) dark matter will dominate, and galaxies will
stop expanding.
e) there was more helium than hydrogen
created in the Big Bang.
Question 17 - 9
In the first few
minutes after
the Big Bang
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a) the universe cooled and formed neutral
matter.
b) the cosmic microwave background
radiation was released.
c) electrons recombined with protons.
d) hydrogen fused into deuterium and
then helium.
e) the universe was governed by one
unified super-force.
Question 17 - 9
In the first few
minutes after
the Big Bang
a) the universe cooled and formed neutral
matter.
b) the cosmic microwave background
radiation was released.
c) electrons recombined with protons.
d) hydrogen fused into deuterium and
then helium.
e) the universe was governed by one
unified super-force.
The production of elements heavier than hydrogen
by nuclear fusion is “primordial nucleosynthesis.”
The amount of deuterium we see today is an
important clue to the density of this early universe.
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Question 17 - 10
The universe
appears flat;
this is
explained by
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a) the Steady State Theory.
b) the Grand Unified Theories.
c) the Inflationary epoch.
d) dark matter.
e) decoupling of matter from radiation.
Question 17 - 10
The universe
appears flat;
this is
explained by
Copyright © 2010 Pearson Education, Inc.
a) the Steady State Theory.
b) the Grand Unified Theories.
c) the Inflationary epoch.
d) dark matter.
e) decoupling of matter from radiation.