Question 1

What mechanism drives the pulsations in Cepheid variables?

Accepted Answer

A)  changes in the rate of core nuclear reactions 
B)  the formation and destruction of sunspots 
C)  the ionization and recombination of hydrogen 
D)  the ionization and recombination of helium 
E)  large rates of mass loss 
A)  changes in the rate of core nuclear reactions 
B)  the formation and destruction of sunspots 
C)  the ionization and recombination of hydrogen 
D)  the ionization and recombination of helium 
E)  large rates of mass loss

Question 2

Once silicon burning begins to fuse iron in the core of a high-mass main-sequence star, it only has a few __________ left to live.

Accepted Answer

A)  seconds 
B)  days 
C)  months 
D)  years 
E)  million years 
A)  seconds 
B)  days 
C)  months 
D)  years 
E)  million years

Question 3

An iron core cannot support a massive main-sequence star because:

Accepted Answer

A)  iron has low nuclear binding energy 
B)  iron is not present in stellar interiors 
C)  iron supplies too much pressure 
D)  iron fusion only occurs in a degenerate core 
E)  iron cannot fuse to make heavier nuclei and produce energy 
A)  iron has low nuclear binding energy 
B)  iron is not present in stellar interiors 
C)  iron supplies too much pressure 
D)  iron fusion only occurs in a degenerate core 
E)  iron cannot fuse to make heavier nuclei and produce energy

Question 4

The acceleration from gravity on the surface of a neutron star can be how large compared to the value on the surface of the Earth? For reference, the typical mass of a neutron star is 2 M $\odot$  and its radius is approximately 10 km.

Accepted Answer

A)  equal in size 
B)  10 times as large 
C)  104 times as large 
D)  107 times as large 
E)  1011 times as large 
A)  equal in size 
B)  10 times as large 
C)  104 times as large 
D)  107 times as large 
E)  1011 times as large

Question 5

Neutron stars are sometimes found in binary systems, where matter overflowing from a companion star and accreting onto the neutron star will produce X-rays and other energetic phenomena.

Accepted Answer

A) True 
 B)False

Question 6

Which of the clusters in this figure are open clusters?

Accepted Answer

A)  Westerlund 2 and M53 
B)  NGC 290 and M9 
C)  NGC 290 and Westerlund 2 
D)  M9 and Westerlund 2 
E)  M53 and NGC 290 
A)  Westerlund 2 and M53 
B)  NGC 290 and M9 
C)  NGC 290 and Westerlund 2 
D)  M9 and Westerlund 2 
E)  M53 and NGC 290

Question 7

The nuclear reaction that releases the most energy per kilogram is:

Accepted Answer

A)  silicon fusing to iron 
B)  oxygen fusing to silicon 
C)  carbon fusing to magnesium 
D)  helium fusing to carbon 
E)  hydrogen fusing to helium 
A)  silicon fusing to iron 
B)  oxygen fusing to silicon 
C)  carbon fusing to magnesium 
D)  helium fusing to carbon 
E)  hydrogen fusing to helium

Question 8

Suppose you measured H-R diagrams for the two star clusters pictured below. Which of the following statements is true?

Accepted Answer

A)  Cluster A is younger than cluster B, but both are the same distance away. 
B)  Cluster A is older and farther away than cluster B. 
C)  Cluster A and cluster B have the same age, but cluster B is closer. 
D)  Cluster A is older and closer than cluster B. 
E)  Cluster A is younger and farther away than cluster B. 
A)  Cluster A is younger than cluster B, but both are the same distance away. 
B)  Cluster A is older and farther away than cluster B. 
C)  Cluster A and cluster B have the same age, but cluster B is closer. 
D)  Cluster A is older and closer than cluster B. 
E)  Cluster A is younger and farther away than cluster B.

Question 9

Describe the physical mechanism that causes pulsations in Cepheid variables.

Accepted Answer

During the contraction phase of the puls

Question 10

List the following H-R diagrams from oldest to youngest.

Accepted Answer

A)  2, 1, 3, 4 
B)  1, 4, 3, 2 
C)  4, 3, 1, 2 
D)  1, 2, 4, 3 
E)  3, 1, 4, 2 
A)  2, 1, 3, 4 
B)  1, 4, 3, 2 
C)  4, 3, 1, 2 
D)  1, 2, 4, 3 
E)  3, 1, 4, 2

What mechanism drives the pulsations in Cepheid variables?

Once silicon burning begins to fuse iron in the core of a high-mass main-sequence star, it only has a few __________ left to live.

An iron core cannot support a massive main-sequence star because:

The acceleration from gravity on the surface of a neutron star can be how large compared to the value on the surface of the Earth? For reference, the typical mass of a neutron star is 2 M _$\odot$ and its radius is approximately 10 km.

Neutron stars are sometimes found in binary systems, where matter overflowing from a companion star and accreting onto the neutron star will produce X-rays and other energetic phenomena.

Which of the clusters in this figure are open clusters?

The nuclear reaction that releases the most energy per kilogram is:

Suppose you measured H-R diagrams for the two star clusters pictured below. Which of the following statements is true?

Describe the physical mechanism that causes pulsations in Cepheid variables.

List the following H-R diagrams from oldest to youngest.

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornmentsmoons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters

Exam 17: Evolution of High-Mass Stars

What mechanism drives the pulsations in Cepheid variables?

Once silicon burning begins to fuse iron in the core of a high-mass main-sequence star, it only has a few __________ left to live.

An iron core cannot support a massive main-sequence star because:

The acceleration from gravity on the surface of a neutron star can be how large compared to the value on the surface of the Earth? For reference, the typical mass of a neutron star is 2 M ⊙\odot⊙ and its radius is approximately 10 km.

Neutron stars are sometimes found in binary systems, where matter overflowing from a companion star and accreting onto the neutron star will produce X-rays and other energetic phenomena.

Which of the clusters in this figure are open clusters?

The nuclear reaction that releases the most energy per kilogram is:

Suppose you measured H-R diagrams for the two star clusters pictured below. Which of the following statements is true?

Describe the physical mechanism that causes pulsations in Cepheid variables.

List the following H-R diagrams from oldest to youngest.

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornmentsmoons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Relativity and Black Holes

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters

The acceleration from gravity on the surface of a neutron star can be how large compared to the value on the surface of the Earth? For reference, the typical mass of a neutron star is 2 M _$\odot$ and its radius is approximately 10 km.