Question 1

How are globular clusters used to test stellar models?

Accepted Answer

Each globular cluster has stars with a r

Question 2

Stars A and B are identical,except that star A has a parallax of 0.1 arcseconds while star B has a parallax of 0.4 arcseconds.How does the brightness of stars A and B compare?

Accepted Answer

Star B is

Question 3

An astronomer studies two globular clusters,A and B.Cluster A has a higher metallicity than cluster B,but their properties are otherwise identical.The astronomer should expect that:

Accepted Answer

A)  cluster A's main sequence turnoff occurs at a higher mass than cluster B. 
B)  cluster A is more distant than cluster B. 
C)  cluster A is older than cluster B. 
D)  cluster A is more massive than cluster B. 
A)  cluster A's main sequence turnoff occurs at a higher mass than cluster B. 
B)  cluster A is more distant than cluster B. 
C)  cluster A is older than cluster B. 
D)  cluster A is more massive than cluster B.

Question 4

Draw an HR diagram and sketch the location of the main sequence,red giant branch,and white dwarfs.

Accepted Answer

The answer of Draw an HR diagram and sketch the...

Question 5

Star A is four times as luminous as star B.Star B's spectrum peaks at 300 nm,while star A's spectrum peaks at 150 nm.How large is the radius of star A compared to star B?

Accepted Answer

A)  1/2 as large 
B)  1/4 as large 
C)  twice as large 
D)  four times as large 
A)  1/2 as large 
B)  1/4 as large 
C)  twice as large 
D)  four times as large

Question 6

Star A has an apparent magnitude of 7,while star B has an apparent magnitude of 12.If star A is four times more luminous than star B,how do the distances of the two stars compare?

Accepted Answer

A)  Star A is 25 times farther than star B. 
B)  Star A is 5 times farther than star B. 
C)  Star A is 25 times closer than star B. 
D)  Star A is 5 times closer than star B. 
A)  Star A is 25 times farther than star B. 
B)  Star A is 5 times farther than star B. 
C)  Star A is 25 times closer than star B. 
D)  Star A is 5 times closer than star B.

Question 7

If the Sun spends 10 billion years on the main sequence,how long will a star 100 times more massive than the Sun spend there?

Accepted Answer

A)  105 years 
B)  3 × 106 years 
C)  109 years 
D)  1011 years 
A)  105 years 
B)  3 × 106 years 
C)  109 years 
D)  1011 years

Question 8

Two stars orbit their common center of mass on circular orbits.Star A is four times more massive than star B.How do their orbital periods compare to each other?

Accepted Answer

A)  Star A has a longer orbital period than star B. 
B)  Star B has a longer orbital period than star A. 
C)  They are the same. 
D)  The orbital periods cannot be determined without knowing their initial velocities. 
A)  Star A has a longer orbital period than star B. 
B)  Star B has a longer orbital period than star A. 
C)  They are the same. 
D)  The orbital periods cannot be determined without knowing their initial velocities.

Question 9

Which of the following combinations of measurements CANNOT be used to determine a star's radius?

Accepted Answer

A)  brightness and peak wavelength 
B)  angular size and distance 
C)  brightness, distance, and temperature 
D)  luminosity and peak wavelength 
A)  brightness and peak wavelength 
B)  angular size and distance 
C)  brightness, distance, and temperature 
D)  luminosity and peak wavelength

Question 10

A star has a surface temperature of 15,000 K.At what wavelength does the star produce the most energy?

Accepted Answer

By Wien's law,the st

How are globular clusters used to test stellar models?

Stars A and B are identical,except that star A has a parallax of 0.1 arcseconds while star B has a parallax of 0.4 arcseconds.How does the brightness of stars A and B compare?

An astronomer studies two globular clusters,A and B.Cluster A has a higher metallicity than cluster B,but their properties are otherwise identical.The astronomer should expect that:

Draw an HR diagram and sketch the location of the main sequence,red giant branch,and white dwarfs.

Star A is four times as luminous as star B.Star B's spectrum peaks at 300 nm,while star A's spectrum peaks at 150 nm.How large is the radius of star A compared to star B?

Star A has an apparent magnitude of 7,while star B has an apparent magnitude of 12.If star A is four times more luminous than star B,how do the distances of the two stars compare?

If the Sun spends 10 billion years on the main sequence,how long will a star 100 times more massive than the Sun spend there?

Two stars orbit their common center of mass on circular orbits.Star A is four times more massive than star B.How do their orbital periods compare to each other?

Which of the following combinations of measurements CANNOT be used to determine a star's radius?

A star has a surface temperature of 15,000 K.At what wavelength does the star produce the most energy?

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

Life and the Search for Habitable Worlds

The Sun As a Star

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

Filters

Exam 11: Measuring the Stars: the Main Sequence and Its Meaning

How are globular clusters used to test stellar models?

Stars A and B are identical,except that star A has a parallax of 0.1 arcseconds while star B has a parallax of 0.4 arcseconds.How does the brightness of stars A and B compare?

An astronomer studies two globular clusters,A and B.Cluster A has a higher metallicity than cluster B,but their properties are otherwise identical.The astronomer should expect that:

Draw an HR diagram and sketch the location of the main sequence,red giant branch,and white dwarfs.

Star A is four times as luminous as star B.Star B's spectrum peaks at 300 nm,while star A's spectrum peaks at 150 nm.How large is the radius of star A compared to star B?

Star A has an apparent magnitude of 7,while star B has an apparent magnitude of 12.If star A is four times more luminous than star B,how do the distances of the two stars compare?

If the Sun spends 10 billion years on the main sequence,how long will a star 100 times more massive than the Sun spend there?

Two stars orbit their common center of mass on circular orbits.Star A is four times more massive than star B.How do their orbital periods compare to each other?

Which of the following combinations of measurements CANNOT be used to determine a star's radius?

A star has a surface temperature of 15,000 K.At what wavelength does the star produce the most energy?

Getting Started: Science, astronomy, and Being Human

A Universe Made, a Universe Discovered

A Universe of Universal Laws

A Universe of Universal Laws

The Architecture and Birth of Planetary Systems

Home Base: Earth and Moon

Sibling Worlds: Mercury, Venus, and Mars

Gas, ice, and Stone: the Outer Planets

Life and the Search for Habitable Worlds

The Sun As a Star

Nursery of the Stars: the Interstellar Medium and Star Formation

To the Graveyard of Stars: the End Points of Stellar Evolution

Down the Rabbit Hole: Relativity and Black Holes

Our City of Stars: the Milky Way

A Universe of Galaxies

The Cosmic Web: the Large-Scale Structure of the Universe

Cosmology

Filters