Question 1

How does Einstein's view of time compare with Newton's view?

Accepted Answer

A) They are virtually the same. 
B) In Newton's model the passage of time is different near a large mass than when away from a large mass. In Einstein's model this is untrue. 
C) In Einstein's model the passage of time is different near a large mass than when away from a large mass. In Newton's model this is untrue. 
D) In Einstein's model of time it is possible to have an effect appear before its cause. In Newton's view this never happens. 
A) They are virtually the same. 
B) In Newton's model the passage of time is different near a large mass than when away from a large mass. In Einstein's model this is untrue. 
C) In Einstein's model the passage of time is different near a large mass than when away from a large mass. In Newton's model this is untrue. 
D) In Einstein's model of time it is possible to have an effect appear before its cause. In Newton's view this never happens.

Question 2

In our description of the universe, what does the word "isotropic" mean?

Accepted Answer

A) Every region is the same as every other region. 
B) The universe looks the same in every direction. 
C) The universe is expanding uniformly at every point. 
D) Every galaxy is moving away from every other galaxy. 
A) Every region is the same as every other region. 
B) The universe looks the same in every direction. 
C) The universe is expanding uniformly at every point. 
D) Every galaxy is moving away from every other galaxy.

Question 3

The ionization energy of a hydrogen atom, that is the energy required to remove the electron from the atom completely, is 13.6 electron volts. Suppose it were 25 electron volts instead. What difference would this make to cosmology?

Accepted Answer

A) None. Individual atoms are much too small to have any effect on the evolution of the universe. 
B) The cosmic microwave background radiation would be hotter than 2.7 kelvins. 
C) The cosmic microwave background radiation would be cooler than 2.7 kelvins. 
D) There would be no cosmic microwave background radiation. 
A) None. Individual atoms are much too small to have any effect on the evolution of the universe. 
B) The cosmic microwave background radiation would be hotter than 2.7 kelvins. 
C) The cosmic microwave background radiation would be cooler than 2.7 kelvins. 
D) There would be no cosmic microwave background radiation.

Question 4

What condition is necessary for the universe to be unbounded (infinite in extent)?

Accepted Answer

A) The density of the universe must be equal to or less than some critical value. 
B) The density of the universe must be equal to or greater than some critical value. 
C) The universe must have no mass in it. 
D) The density of the universe must be exactly equal to some critical value. 
A) The density of the universe must be equal to or less than some critical value. 
B) The density of the universe must be equal to or greater than some critical value. 
C) The universe must have no mass in it. 
D) The density of the universe must be exactly equal to some critical value.

Question 5

If the universal expansion is accelerating, how does this affect the age of the universe derived from the Hubble law?

Accepted Answer

A) Acceleration has no effect on the derived age. 
B) The derived age is higher than if the expansion is constant. 
C) It can either increase of decrease the derived age, depending on the density of the universe and the resulting curvature of space. 
D) The derived age is lower than if the expansion is constant. 
A) Acceleration has no effect on the derived age. 
B) The derived age is higher than if the expansion is constant. 
C) It can either increase of decrease the derived age, depending on the density of the universe and the resulting curvature of space. 
D) The derived age is lower than if the expansion is constant.

Question 6

The conditions in the early universe, when the universe suddenly became transparent to radiation, in terms of age t, peak background wavelength λ, and equivalent temperature T, were:

Accepted Answer

A) t = 3 minutes, λ = 0.3 μm, near UV, and T = 107 K. 
B) t = 380,000 years, λ = 1 μm, infrared, and T = 3000 K. 
C) t = 3 × 1011 years, λ = 1 mm, microwaves, and T = 3 K. 
D) The universe was never dominated by radiation, because matter has always dominated by generating the gravitational field into which the universe has expanded. 
A) t = 3 minutes, λ = 0.3 μm, near UV, and T = 107 K. 
B) t = 380,000 years, λ = 1 μm, infrared, and T = 3000 K. 
C) t = 3 × 1011 years, λ = 1 mm, microwaves, and T = 3 K. 
D) The universe was never dominated by radiation, because matter has always dominated by generating the gravitational field into which the universe has expanded.

Question 7

An object has a lookback time of 1 billion years. Assuming it is nonrelativistic, and that the Hubble constant is 22.4 km/s/Mly, what is its cosmological redshift?

Accepted Answer

A) 0.074 
B) 0.126 
C) 0.546 
D) 1.89 
A) 0.074 
B) 0.126 
C) 0.546 
D) 1.89

Question 8

The density parameter Ω0 measures the total mass-energy density in the universe from all sources as a function of the critical density. How much of this is from ordinary atomic matter and how much from dark matter?

Accepted Answer

A) About 5% is from ordinary matter and another 26% from dark matter. 
B) About 24% is from ordinary matter and the remaining 96% is from dark matter. 
C) About 50% is contributed by each of these sources. 
D) About 96% is from atomic matter and the remaining 4% is from dark matter. 
A) About 5% is from ordinary matter and another 26% from dark matter. 
B) About 24% is from ordinary matter and the remaining 96% is from dark matter. 
C) About 50% is contributed by each of these sources. 
D) About 96% is from atomic matter and the remaining 4% is from dark matter.

How does Einstein's view of time compare with Newton's view?

In our description of the universe, what does the word "isotropic" mean?

The ionization energy of a hydrogen atom, that is the energy required to remove the electron from the atom completely, is 13.6 electron volts. Suppose it were 25 electron volts instead. What difference would this make to cosmology?

What condition is necessary for the universe to be unbounded (infinite in extent)?

If the universal expansion is accelerating, how does this affect the age of the universe derived from the Hubble law?

The conditions in the early universe, when the universe suddenly became transparent to radiation, in terms of age t, peak background wavelength λ, and equivalent temperature T, were:

An object has a lookback time of 1 billion years. Assuming it is nonrelativistic, and that the Hubble constant is 22.4 km/s/Mly, what is its cosmological redshift?

The density parameter Ω₀ measures the total mass-energy density in the universe from all sources as a function of the critical density. How much of this is from ordinary atomic matter and how much from dark matter?

Astronomy and the Universe

Knowing the Heavens

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

The Nature of Light

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturn: Lords of the Planets

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Asteroids, Comets, and Impacts

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Exploring the Early Universe

The Search for Extraterrestrial Life

Filters

Exam 25: Cosmology: The Origin and Evolution of the Universe

How does Einstein's view of time compare with Newton's view?

In our description of the universe, what does the word "isotropic" mean?

The ionization energy of a hydrogen atom, that is the energy required to remove the electron from the atom completely, is 13.6 electron volts. Suppose it were 25 electron volts instead. What difference would this make to cosmology?

What condition is necessary for the universe to be unbounded (infinite in extent)?

If the universal expansion is accelerating, how does this affect the age of the universe derived from the Hubble law?

The conditions in the early universe, when the universe suddenly became transparent to radiation, in terms of age t, peak background wavelength λ, and equivalent temperature T, were:

An object has a lookback time of 1 billion years. Assuming it is nonrelativistic, and that the Hubble constant is 22.4 km/s/Mly, what is its cosmological redshift?

The density parameter Ω0 measures the total mass-energy density in the universe from all sources as a function of the critical density. How much of this is from ordinary atomic matter and how much from dark matter?

Astronomy and the Universe

Knowing the Heavens

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

The Nature of Light

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturn: Lords of the Planets

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Asteroids, Comets, and Impacts

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Exploring the Early Universe

The Search for Extraterrestrial Life

Filters

The density parameter Ω₀ measures the total mass-energy density in the universe from all sources as a function of the critical density. How much of this is from ordinary atomic matter and how much from dark matter?