Question 1

Figure 18-12 (for the following questions) The re-ionization of the Universe occurredclosest to ____ degrees Kelvin.

Accepted Answer

A)  tens of thousands of 
B)  thousands of 
C)  hundreds of 
D)  tens of 
E)  less than ten 
A)  tens of thousands of 
B)  thousands of 
C)  hundreds of 
D)  tens of 
E)  less than ten D

Question 2

Figure 18-12 (for the following questions) The Universe had a temperature of a few hundred million degrees K at approximately ____ after the big bang.

Accepted Answer

A)  one second 
B)  one minute 
C)  one hour 
D)  one day 
E)  one year 
A)  one second 
B)  one minute 
C)  one hour 
D)  one day 
E)  one year C

Question 3

When matter and antimatter particles combine, the two particles annihilate each other and convert their mass into energy in the form of two gamma rays.

Accepted Answer

A) True 
 B)False  True

Question 4

In the very first phase after the big bang, when the Universe was about a microsecond old, space was filled with____.

Accepted Answer

A)  high-energy photons 
B)  protons and antiprotons 
C)  protons, neutrons, electrons, and positrons (anti-electrons) 
D)  electrons, and positrons (anti-electrons) 
E)  protons, neutrons, electrons 
A)  high-energy photons 
B)  protons and antiprotons 
C)  protons, neutrons, electrons, and positrons (anti-electrons) 
D)  electrons, and positrons (anti-electrons) 
E)  protons, neutrons, electrons

Question 5

The "big bang" was an explosion of material that created galaxies flying away from the center of the explosion.

Accepted Answer

A) True 
 B)False

Question 6

Ordinary matter makes up approximately ____percent of the critical density of the Universe.

Accepted Answer

A)  0.1 
B)  1 
C)  4.5 
D)  10 
E)  50 
A)  0.1 
B)  1 
C)  4.5 
D)  10 
E)  50

Question 7

The density of the Universe comes from baryonic matter, non-baryonic dark matter, and dark energy. What percentage of the density of the Universe do each of the three represent?

Accepted Answer

The density of the Universe co

Question 8

What are the four fundamental forces in the Universe and how did they affect the first steps of the big bang and the inflation of the Universe?

Accepted Answer

The four fundamental forces in the Unive

Question 9

Dark energy accounts for about 70% of the critical density of the Universe.

Accepted Answer

A) True 
 B)False

Question 10

The fact that the cosmic microwave background radiation has almost exactly the same temperature in every direction is referred to as the _______________ problem.

Accepted Answer

The answer of The fact that the cosmic microwave background...

Question 11

The separation of the strong force and the electroweak force ____.

Accepted Answer

A)  provided the energy for a rapid inflation of the early Universe 
B)  created the cosmic microwave background radiation 
C)  balanced the critical density of the Universe to solve the flatness problem 
D)  created dark matter 
E)  created dark energy 
A)  provided the energy for a rapid inflation of the early Universe 
B)  created the cosmic microwave background radiation 
C)  balanced the critical density of the Universe to solve the flatness problem 
D)  created dark matter 
E)  created dark energy

Question 12

The Hubble time is____.

Accepted Answer

A)  an estimate of the age of the Universe 
B)  the time needed for a galaxy to travel 1 Mpc 
C)  not connected to Hubble law of galactic redshifts 
D)  the time for light to cross the Universe 
E)  the time needed for galaxies to form 
A)  an estimate of the age of the Universe 
B)  the time needed for a galaxy to travel 1 Mpc 
C)  not connected to Hubble law of galactic redshifts 
D)  the time for light to cross the Universe 
E)  the time needed for galaxies to form

Question 13

The proper interpretation of a what a galaxy's redshift measures is ____.

Accepted Answer

A)  its motion in space toward the observer 
B)  its motion in space away from the big bang 
C)  the stretching of space between the galaxy and the observer 
D)  the contraction of space between the galaxy and the observer 
E)  the stretching of space between the galaxy and the big bang 
A)  its motion in space toward the observer 
B)  its motion in space away from the big bang 
C)  the stretching of space between the galaxy and the observer 
D)  the contraction of space between the galaxy and the observer 
E)  the stretching of space between the galaxy and the big bang

Question 14

In the early universe, the electromagnetic and strong nuclear forces were joined together to make the electrostrong force.

Accepted Answer

A) True 
 B)False

Question 15

Why did the big bang only create hydrogen, helium, and trace amounts of lithium?

Accepted Answer

Atoms with an atomic weight of 5 or 8 ar

Question 16

The gas created by the big bang was so hot that it was completely _______________ until the Universe was no longer radiation-dominated.

Accepted Answer

The answer of The gas created by the big bang...

Question 17

Dark energy is the term used to describe ____.

Accepted Answer

A)  the pressure inflating "voids" in the distribution of galaxies 
B)  radiation from antimatter and non-baryonic matter 
C)  a component of the cosmic microwave background radiation 
D)  an effect that works with gravity to decelerate the expansion of the Universe 
E)  an effect that works against gravity to accelerate the expansion of the Universe 
A)  the pressure inflating "voids" in the distribution of galaxies 
B)  radiation from antimatter and non-baryonic matter 
C)  a component of the cosmic microwave background radiation 
D)  an effect that works with gravity to decelerate the expansion of the Universe 
E)  an effect that works against gravity to accelerate the expansion of the Universe

Question 18

The expansion of the Universe is accelerating.

Accepted Answer

A) True 
 B)False

Question 19

Dark matter must be ____.

Accepted Answer

A)  baryonic 
B)  non-baryonic 
C)  neutral 
D)  WIMPs 
E)  isochronic 
A)  baryonic 
B)  non-baryonic 
C)  neutral 
D)  WIMPs 
E)  isochronic

Question 20

The Hubble time only describes a Universe that is ____.

Accepted Answer

A)  flat 
B)  totally open 
C)  totally closed 
D)  partially open 
E)  partially closed 
A)  flat 
B)  totally open 
C)  totally closed 
D)  partially open 
E)  partially closed

Exam 18: Modern Cosmology

Figure 18-12 (for the following questions) The re-ionization of the Universe occurredclosest to ____ degrees Kelvin.

Figure 18-12 (for the following questions) The Universe had a temperature of a few hundred million degrees K at approximately ____ after the big bang.

When matter and antimatter particles combine, the two particles annihilate each other and convert their mass into energy in the form of two gamma rays.

In the very first phase after the big bang, when the Universe was about a microsecond old, space was filled with____.

The "big bang" was an explosion of material that created galaxies flying away from the center of the explosion.

Ordinary matter makes up approximately ____percent of the critical density of the Universe.

The density of the Universe comes from baryonic matter, non-baryonic dark matter, and dark energy. What percentage of the density of the Universe do each of the three represent?

What are the four fundamental forces in the Universe and how did they affect the first steps of the big bang and the inflation of the Universe?

Dark energy accounts for about 70% of the critical density of the Universe.

The fact that the cosmic microwave background radiation has almost exactly the same temperature in every direction is referred to as the _______________ problem.

The separation of the strong force and the electroweak force ____.

The Hubble time is____.

The proper interpretation of a what a galaxy's redshift measures is ____.

In the early universe, the electromagnetic and strong nuclear forces were joined together to make the electrostrong force.

Why did the big bang only create hydrogen, helium, and trace amounts of lithium?

The gas created by the big bang was so hot that it was completely _______________ until the Universe was no longer radiation-dominated.

Dark energy is the term used to describe ____.

The expansion of the Universe is accelerating.

Dark matter must be ____.

The Hubble time only describes a Universe that is ____.

Here and Now

A Users Guide to the Sky

Moon Phases and Eclipses

Origins of Modern Astronomy

Gravity

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Interstellar Medium

Formation and Structure of Stars

Stellar Evolution

Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies

Supermassive Black Holes and Active Galaxies

Origin of the Solar System and Extrasolar Planets

Earth the Active Planet

The Moon and Mercury

Venus and Mars

Jupiter and Saturn

Uranus Neptune Pluto and the Kuiper Belt

Meteorites Asteroids and Comets

Astrobiology

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