Question 1

Calculate the age of the universe if Hubble's constant,H0,is 73 km/s/Mpc,and the expansion is assumed to be uniform.

Accepted Answer

A)  2.27 million years 
B)  1.43 billion years 
C)  13.4 billion years 
D)  1340 billion years 
A)  2.27 million years 
B)  1.43 billion years 
C)  13.4 billion years 
D)  1340 billion years C

Question 2

What kind of curvature (geometry of space)does the universe have if the universe is unbounded (density < critical density)?

Accepted Answer

A)  Flat 
B)  Closed 
C)  Open 
D)  Curvature does not depend on density. 
A)  Flat 
B)  Closed 
C)  Open 
D)  Curvature does not depend on density. C

Question 3

Which of the following statements correctly describes the universe for the entire first 380,000 years of its life?

Accepted Answer

A)  All of the fundamental forces were united into one force. 
B)  It was filled with free quarks (not confined inside neutrons or protons). 
C)  It was a sea of nuclear reactions occurring at a gradually decreasing rate. 
D)  It was opaque. 
A)  All of the fundamental forces were united into one force. 
B)  It was filled with free quarks (not confined inside neutrons or protons). 
C)  It was a sea of nuclear reactions occurring at a gradually decreasing rate. 
D)  It was opaque. D

Question 4

If one galaxy is twice as far from Earth as another,its velocity will be

Accepted Answer

A)  twice as much. 
B)  four times as much. 
C)  one-half as much. 
D)  one-fourth as much. 
A)  twice as much. 
B)  four times as much. 
C)  one-half as much. 
D)  one-fourth as much.

Question 5

If the universe were found to have a positive curvature,than space would be open rather than closed or flat.

Accepted Answer

A) True 
 B)False

Question 6

The strongest of the fundamental forces of the universe is gravity.

Accepted Answer

A) True 
 B)False

Question 7

The Andromeda Galaxy has an overall blue shift meaning that it is moving toward the Milky Way Galaxy.

Accepted Answer

A) True 
 B)False

Question 8

At the start of the Big Bang,all of the fundamental forces were unified and behaved like a single force.As the universe expanded and cooled during the Big Bang,which was the first force to "freeze out" as a separate force?

Accepted Answer

A)  Electromagnetic force 
B)  Weak nuclear force 
C)  Gravity 
D)  Strong nuclear force 
A)  Electromagnetic force 
B)  Weak nuclear force 
C)  Gravity 
D)  Strong nuclear force

Question 9

What is the "cosmological redshift"?

Accepted Answer

A)  The stretching of wavelengths of photons by the Doppler shift,because they are emitted by galaxies that are moving away from us 
B)  The loss of energy of photons as they interact with virtual particles in the vacuum,so that their wavelengths gradually increase as they travel toward us through space 
C)  The stretching of the wavelengths of photons as they travel through expanding space 
D)  The stretching of the wavelengths of photons as they pass through absorbing matter in galaxies between us and the emitting galaxy 
A)  The stretching of wavelengths of photons by the Doppler shift,because they are emitted by galaxies that are moving away from us 
B)  The loss of energy of photons as they interact with virtual particles in the vacuum,so that their wavelengths gradually increase as they travel toward us through space 
C)  The stretching of the wavelengths of photons as they travel through expanding space 
D)  The stretching of the wavelengths of photons as they pass through absorbing matter in galaxies between us and the emitting galaxy

Question 10

Recent satellite missions have confirmed the lumpiness of the cosmic microwave background,which helps explain the current structure of the universe.

Accepted Answer

A) True 
 B)False

Question 11

What significant event occurred 380,000 years after the start of the Big Bang?

Accepted Answer

A)  The production of helium ceased. 
B)  All of the galaxies we see today formed. 
C)  Quarks became confined in nuclei. 
D)  Electrons and nuclei combined to form neutral atoms. 
A)  The production of helium ceased. 
B)  All of the galaxies we see today formed. 
C)  Quarks became confined in nuclei. 
D)  Electrons and nuclei combined to form neutral atoms.

Question 12

What is the cosmological principle and what does it mean for the universe?

Accepted Answer

The cosmological principle ass

Question 13

There is far more helium in the universe than could have been created by hydrogen fusion in stars alone.

Accepted Answer

A) True 
 B)False

Question 14

What is the era of recombination and what happened to the universe at that time?

Accepted Answer

The epoch when atoms first formed at t =

Question 15

Temperature variations in the early universe appear as "hot spots" in the cosmic microwave background.The apparent size of these spots depends on the curvature of space.

Accepted Answer

A) True 
 B)False

Question 16

A theory that describes how the fundamental forces in the universe are combined and explains the interactions of everything in the universe is

Accepted Answer

A)  a grand unified theory (GUT). 
B)  a theory of everything (TO
E) . 
C)  neither of these. 
D)  both of these. 
A)  a grand unified theory (GUT). 
B)  a theory of everything (TO
E) . 
C)  neither of these. 
D)  both of these.

Question 17

Which of the following sources contributes the greatest number of photons to the general radiation background in our universe?

Accepted Answer

A)  The cosmic microwave background,the remnant of the Big Bang 
B)  The very large number of average solar-type cool stars,contributing vast numbers of visible and infrared photons 
C)  Atomic hydrogen,which is very abundant throughout the universe,contributing mainly 21-cm radio photons. 
D)  Extremely hot intergalactic gas in clusters of galaxies,producing copious numbers of X-ray photons 
A)  The cosmic microwave background,the remnant of the Big Bang 
B)  The very large number of average solar-type cool stars,contributing vast numbers of visible and infrared photons 
C)  Atomic hydrogen,which is very abundant throughout the universe,contributing mainly 21-cm radio photons. 
D)  Extremely hot intergalactic gas in clusters of galaxies,producing copious numbers of X-ray photons

Question 18

What is Olbers's paradox and how is it resolved?

Accepted Answer

Olbers's paradox asks the question: "Why

Question 19

The Hubble distance-velocity relationship states that

Accepted Answer

A)  all galaxies are being pulled toward a central gravitational attractor in the universe,with the galaxies closest to the center traveling the fastest. 
B)  the farther away a galaxy is from the Local Group of galaxies,the faster it is traveling toward this group. 
C)  the farther away a galaxy is from our Galaxy,the faster it appears to be traveling away from it. 
D)  all galaxies are being repelled by the pressure from the hot central "engine" of the universe,with the ones closest to the center traveling the fastest. 
A)  all galaxies are being pulled toward a central gravitational attractor in the universe,with the galaxies closest to the center traveling the fastest. 
B)  the farther away a galaxy is from the Local Group of galaxies,the faster it is traveling toward this group. 
C)  the farther away a galaxy is from our Galaxy,the faster it appears to be traveling away from it. 
D)  all galaxies are being repelled by the pressure from the hot central "engine" of the universe,with the ones closest to the center traveling the fastest.

Question 20

What do astronomers mean when they talk about dark energy?

Accepted Answer

The missing density of the universe as m

Calculate the age of the universe if Hubble's constant,H₀,is 73 km/s/Mpc,and the expansion is assumed to be uniform.

What kind of curvature (geometry of space)does the universe have if the universe is unbounded (density < critical density)?

Which of the following statements correctly describes the universe for the entire first 380,000 years of its life?

If one galaxy is twice as far from Earth as another,its velocity will be

If the universe were found to have a positive curvature,than space would be open rather than closed or flat.

The strongest of the fundamental forces of the universe is gravity.

The Andromeda Galaxy has an overall blue shift meaning that it is moving toward the Milky Way Galaxy.

At the start of the Big Bang,all of the fundamental forces were unified and behaved like a single force.As the universe expanded and cooled during the Big Bang,which was the first force to "freeze out" as a separate force?

What is the "cosmological redshift"?

Recent satellite missions have confirmed the lumpiness of the cosmic microwave background,which helps explain the current structure of the universe.

What significant event occurred 380,000 years after the start of the Big Bang?

What is the cosmological principle and what does it mean for the universe?

There is far more helium in the universe than could have been created by hydrogen fusion in stars alone.

What is the era of recombination and what happened to the universe at that time?

Temperature variations in the early universe appear as "hot spots" in the cosmic microwave background.The apparent size of these spots depends on the curvature of space.

A theory that describes how the fundamental forces in the universe are combined and explains the interactions of everything in the universe is

Which of the following sources contributes the greatest number of photons to the general radiation background in our universe?

What is Olbers's paradox and how is it resolved?

The Hubble distance-velocity relationship states that

What do astronomers mean when they talk about dark energy?

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

Inferring Patterns in Star Life Cycles

Predicting the Violent End of the Largest Stars

Exploring Our Galaxy

Investigating Other Galaxies

Filters

Exam 15: Observing the Evolution of the Universe

Calculate the age of the universe if Hubble's constant,H0,is 73 km/s/Mpc,and the expansion is assumed to be uniform.

What kind of curvature (geometry of space)does the universe have if the universe is unbounded (density < critical density)?

Which of the following statements correctly describes the universe for the entire first 380,000 years of its life?

If one galaxy is twice as far from Earth as another,its velocity will be

If the universe were found to have a positive curvature,than space would be open rather than closed or flat.

The strongest of the fundamental forces of the universe is gravity.

The Andromeda Galaxy has an overall blue shift meaning that it is moving toward the Milky Way Galaxy.

At the start of the Big Bang,all of the fundamental forces were unified and behaved like a single force.As the universe expanded and cooled during the Big Bang,which was the first force to "freeze out" as a separate force?

What is the "cosmological redshift"?

Recent satellite missions have confirmed the lumpiness of the cosmic microwave background,which helps explain the current structure of the universe.

What significant event occurred 380,000 years after the start of the Big Bang?

What is the cosmological principle and what does it mean for the universe?

There is far more helium in the universe than could have been created by hydrogen fusion in stars alone.

What is the era of recombination and what happened to the universe at that time?

Temperature variations in the early universe appear as "hot spots" in the cosmic microwave background.The apparent size of these spots depends on the curvature of space.

A theory that describes how the fundamental forces in the universe are combined and explains the interactions of everything in the universe is

Which of the following sources contributes the greatest number of photons to the general radiation background in our universe?

What is Olbers's paradox and how is it resolved?

The Hubble distance-velocity relationship states that

What do astronomers mean when they talk about dark energy?

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

Inferring Patterns in Star Life Cycles

Predicting the Violent End of the Largest Stars

Exploring Our Galaxy

Investigating Other Galaxies

Filters

Calculate the age of the universe if Hubble's constant,H₀,is 73 km/s/Mpc,and the expansion is assumed to be uniform.