Question 1

If a certain star shows a strong absorption spectrum in hydrogen Balmer lines,the surface temperature of the star is hot enough that collisions between atoms there:

Accepted Answer

A)  ionize virtually all of the hydrogen atoms. 
B)  promote electrons in many hydrogen atoms to the n = 2 energy level. 
C)  promote electrons in many hydrogen atoms to the n = 3 energy level. 
D)  convert many helium atoms to hydrogen atoms. 
A)  ionize virtually all of the hydrogen atoms. 
B)  promote electrons in many hydrogen atoms to the n = 2 energy level. 
C)  promote electrons in many hydrogen atoms to the n = 3 energy level. 
D)  convert many helium atoms to hydrogen atoms. B

Question 2

A star has an absolute magnitude M = 1.69 and an apparent magnitude m = 1.04.How far away is this star? (Hint: this question does not require a detailed calculation.)

Accepted Answer

A)  24.2 ly 
B)  43.2 ly 
C)  59.7 ly 
D)  160.2 ly 
A)  24.2 ly 
B)  43.2 ly 
C)  59.7 ly 
D)  160.2 ly A

Question 3

The star Elnath is classified as B7 III and the star Al Na'ir is classified as B7 IV.Compared with Al Na'ir,Elnath has about the same:

Accepted Answer

A)  surface temperature but is intrinsically much fainter. 
B)  intrinsic brightness but is considerably cooler. 
C)  surface temperature but is intrinsically much brighter. 
D)  intrinsic brightness but is considerably hotter. 
A)  surface temperature but is intrinsically much fainter. 
B)  intrinsic brightness but is considerably cooler. 
C)  surface temperature but is intrinsically much brighter. 
D)  intrinsic brightness but is considerably hotter. C

Question 4

White dwarfs are not included in the luminosity classification because they are:

Accepted Answer

A)  not yet active stars; they have not yet begun nuclear reactions. 
B)  no longer producing energy by nuclear reactions. 
C)  no longer radiating energy away. 
D)  too small. 
A)  not yet active stars; they have not yet begun nuclear reactions. 
B)  no longer producing energy by nuclear reactions. 
C)  no longer radiating energy away. 
D)  too small.

Question 5

The spectral luminosity class of the star Spica is B1 V,and that of the starƮ Ceti is G8 V.From this information,we know thatƮ Ceti is _____ Spica.

Accepted Answer

A)  cooler but has the same luminosity as 
B)  cooler and has a lower luminosity than 
C)  hotter but has the same luminosity as 
D)  hotter and has a lower luminosity than 
A)  cooler but has the same luminosity as 
B)  cooler and has a lower luminosity than 
C)  hotter but has the same luminosity as 
D)  hotter and has a lower luminosity than

Question 6

As you move upward and to the right on the H-R diagram,stars become:

Accepted Answer

A)  hotter and brighter. 
B)  hotter and dimmer. 
C)  cooler and dimmer. 
D)  cooler and brighter. 
A)  hotter and brighter. 
B)  hotter and dimmer. 
C)  cooler and dimmer. 
D)  cooler and brighter.

Question 7

Two of the brightest stars in Orion are Betelgeuse (apparent magnitude = 0.45)and Rigel (apparent magnitude = 0.15).From this information,you can determine that Betelgeuse is:

Accepted Answer

A)  brighter than Rigel. 
B)  bigger than Rigel. 
C)  farther away than Rigel. 
D)  None of the answers is correct.. 
A)  brighter than Rigel. 
B)  bigger than Rigel. 
C)  farther away than Rigel. 
D)  None of the answers is correct..

Question 8

Luminosity is measured in:

Accepted Answer

A)  watts. 
B)  watts per second. 
C)  watts per square meter. 
D)  parsecs. 
A)  watts. 
B)  watts per second. 
C)  watts per square meter. 
D)  parsecs.

Question 9

A red supergiant star is found to have a surface temperature of 2500 K and a luminosity 100,000 times that of the Sun.Use the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.,to determine its approximate radius compared with that of the Sun.

Accepted Answer

A)  about 10 times larger 
B)  about 100 times larger 
C)  about 1000 times larger 
D)  almost the same 
A)  about 10 times larger 
B)  about 100 times larger 
C)  about 1000 times larger 
D)  almost the same

Question 10

Which spectral classification letter signifies the hottest stellar surface temperature?

Accepted Answer

A)  G 
B)  A 
C)  K 
D)  B 
A)  G 
B)  A 
C)  K 
D)  B

Question 11

The following expressions are parameters of stars that astronomers obtained from their measurements.Which of these conclusions is obviously NOT correct,based on the positions of these stars on the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.? (L⊙ and R⊙ are the luminosity and radius of the Sun,respectively.)

Accepted Answer

A)  luminosity = L⊙, radius = R⊙, temperature = 6000 K; conclusion: main-sequence star 
B)  luminosity = 10⁴ L⊙, radius = 100 R⊙, temperature = 5000 K; conclusion: red giant star 
C)  luminosity = L⊙, radius = 1/10 R⊙, temperature = 20,000 K; conclusion: white dwarf star 
D)  luminosity = 1/100 L⊙, radius = 1/100 R⊙, temperature = 20,000 K; conclusion: white dwarf star 
A)  luminosity = L⊙, radius = R⊙, temperature = 6000 K; conclusion: main-sequence star 
B)  luminosity = 10⁴ L⊙, radius = 100 R⊙, temperature = 5000 K; conclusion: red giant star 
C)  luminosity = L⊙, radius = 1/10 R⊙, temperature = 20,000 K; conclusion: white dwarf star 
D)  luminosity = 1/100 L⊙, radius = 1/100 R⊙, temperature = 20,000 K; conclusion: white dwarf star

Question 12

For most stars,the:

Accepted Answer

A)  absolute magnitude is a larger number than the apparent magnitude. 
B)  apparent magnitude is a larger number than the absolute magnitude. 
C)  absolute magnitude and the apparent magnitude are numerically equal. 
D)  chances are about even of the apparent magnitude being larger or the absolute magnitude being larger. 
A)  absolute magnitude is a larger number than the apparent magnitude. 
B)  apparent magnitude is a larger number than the absolute magnitude. 
C)  absolute magnitude and the apparent magnitude are numerically equal. 
D)  chances are about even of the apparent magnitude being larger or the absolute magnitude being larger.

Question 13

If you look out at a clear night sky with the unaided eye,the faintest stars you can see have magnitudes around:

Accepted Answer

A)  -6. 
B)  0. 
C)  +6. 
D)  +12. 
A)  -6. 
B)  0. 
C)  +6. 
D)  +12.

Question 14

The spectral luminosity class of the star α Arae is B2 V,and that of π Herculi is K3 II.Using only this information,without referring to tables or diagrams,we can tell that α Arae is:

Accepted Answer

A)  hotter but intrinsically fainter than π Herculi. 
B)  hotter than π Herculi. 
C)  cooler and intrinsically fainter than π Herculi. 
D)  cooler than π Herculi. 
A)  hotter but intrinsically fainter than π Herculi. 
B)  hotter than π Herculi. 
C)  cooler and intrinsically fainter than π Herculi. 
D)  cooler than π Herculi.

Question 15

Which major perturbation can occur to a close binary system and radically alter the evolution and behavior of the two individual stars?

Accepted Answer

A)  gravitational disturbance of one star's motion by its companion to force it to move in an orbit 
B)  transfer of matter from one star to its companion 
C)  heating of the localized areas of the atmosphere of one star by its companion 
D)  eclipsing of the light from one star by the other when viewed from Earth 
A)  gravitational disturbance of one star's motion by its companion to force it to move in an orbit 
B)  transfer of matter from one star to its companion 
C)  heating of the localized areas of the atmosphere of one star by its companion 
D)  eclipsing of the light from one star by the other when viewed from Earth

Question 16

Compared with a star in the middle of the Hertzsprung-Russell diagram,a star in the upper right of the diagram is:

Accepted Answer

A)  fainter. 
B)  hotter. 
C)  larger. 
D)  nonexistent because there are no stars that appear in the upper right of the diagram. 
A)  fainter. 
B)  hotter. 
C)  larger. 
D)  nonexistent because there are no stars that appear in the upper right of the diagram.

Question 17

How many electrons are missing from the ionized silicon atom Si IV?

Accepted Answer

A)  3 
B)  1 
C)  4 
D)  5 
A)  3 
B)  1 
C)  4 
D)  5

Question 18

Which statement comparing the Sun with the giant stars is NOT true? (Refer to Figure 10-10,Comins,Discovering the Essential Universe,6th ed.)

Accepted Answer

A)  The giant stars are more luminous than the Sun. 
B)  The giant stars are larger than the Sun. 
C)  The giant stars are hotter than the Sun. 
D)  The giant stars have smaller absolute magnitudes than the Sun. 
A)  The giant stars are more luminous than the Sun. 
B)  The giant stars are larger than the Sun. 
C)  The giant stars are hotter than the Sun. 
D)  The giant stars have smaller absolute magnitudes than the Sun.

Question 19

A star of apparent magnitude -1.5 appears _____ than a star of apparent magnitude +2.0.

Accepted Answer

A)  farther away 
B)  fainter 
C)  brighter 
D)  either brighter or fainter, depending on the distance to the stars, 
A)  farther away 
B)  fainter 
C)  brighter 
D)  either brighter or fainter, depending on the distance to the stars,

Question 20

An astronomer is measuring the brightness of a particular star through a telescope,using different filters in the visual (yellow-green),violet,and ultraviolet regions.What is the name of the technique being used by this astronomer?

Accepted Answer

A)  spectroscopy 
B)  geometry 
C)  interferometry 
D)  photometry 
A)  spectroscopy 
B)  geometry 
C)  interferometry 
D)  photometry

If a certain star shows a strong absorption spectrum in hydrogen Balmer lines,the surface temperature of the star is hot enough that collisions between atoms there:

A star has an absolute magnitude M = 1.69 and an apparent magnitude m = 1.04.How far away is this star? (Hint: this question does not require a detailed calculation.)

The star Elnath is classified as B7 III and the star Al Na'ir is classified as B7 IV.Compared with Al Na'ir,Elnath has about the same:

White dwarfs are not included in the luminosity classification because they are:

The spectral luminosity class of the star Spica is B1 V,and that of the starƮ Ceti is G8 V.From this information,we know thatƮ Ceti is _____ Spica.

As you move upward and to the right on the H-R diagram,stars become:

Two of the brightest stars in Orion are Betelgeuse (apparent magnitude = 0.45)and Rigel (apparent magnitude = 0.15).From this information,you can determine that Betelgeuse is:

Luminosity is measured in:

A red supergiant star is found to have a surface temperature of 2500 K and a luminosity 100,000 times that of the Sun.Use the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.,to determine its approximate radius compared with that of the Sun.

Which spectral classification letter signifies the hottest stellar surface temperature?

For most stars,the:

If you look out at a clear night sky with the unaided eye,the faintest stars you can see have magnitudes around:

The spectral luminosity class of the star α Arae is B2 V,and that of π Herculi is K3 II.Using only this information,without referring to tables or diagrams,we can tell that α Arae is:

Which major perturbation can occur to a close binary system and radically alter the evolution and behavior of the two individual stars?

Compared with a star in the middle of the Hertzsprung-Russell diagram,a star in the upper right of the diagram is:

How many electrons are missing from the ionized silicon atom Si IV?

Which statement comparing the Sun with the giant stars is NOT true? (Refer to Figure 10-10,Comins,Discovering the Essential Universe,6th ed.)

A star of apparent magnitude -1.5 appears _____ than a star of apparent magnitude +2.0.

An astronomer is measuring the brightness of a particular star through a telescope,using different filters in the visual (yellow-green),violet,and ultraviolet regions.What is the name of the technique being used by this astronomer?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters

Exam 10: Characterizing Stars

If a certain star shows a strong absorption spectrum in hydrogen Balmer lines,the surface temperature of the star is hot enough that collisions between atoms there:

A star has an absolute magnitude M = 1.69 and an apparent magnitude m = 1.04.How far away is this star? (Hint: this question does not require a detailed calculation.)

The star Elnath is classified as B7 III and the star Al Na'ir is classified as B7 IV.Compared with Al Na'ir,Elnath has about the same:

White dwarfs are not included in the luminosity classification because they are:

The spectral luminosity class of the star Spica is B1 V,and that of the starƮ Ceti is G8 V.From this information,we know thatƮ Ceti is _____ Spica.

As you move upward and to the right on the H-R diagram,stars become:

Two of the brightest stars in Orion are Betelgeuse (apparent magnitude = 0.45)and Rigel (apparent magnitude = 0.15).From this information,you can determine that Betelgeuse is:

Luminosity is measured in:

A red supergiant star is found to have a surface temperature of 2500 K and a luminosity 100,000 times that of the Sun.Use the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.,to determine its approximate radius compared with that of the Sun.

Which spectral classification letter signifies the hottest stellar surface temperature?

For most stars,the:

If you look out at a clear night sky with the unaided eye,the faintest stars you can see have magnitudes around:

The spectral luminosity class of the star α Arae is B2 V,and that of π Herculi is K3 II.Using only this information,without referring to tables or diagrams,we can tell that α Arae is:

Which major perturbation can occur to a close binary system and radically alter the evolution and behavior of the two individual stars?

Compared with a star in the middle of the Hertzsprung-Russell diagram,a star in the upper right of the diagram is:

How many electrons are missing from the ionized silicon atom Si IV?

Which statement comparing the Sun with the giant stars is NOT true? (Refer to Figure 10-10,Comins,Discovering the Essential Universe,6th ed.)

A star of apparent magnitude -1.5 appears _____ than a star of apparent magnitude +2.0.

An astronomer is measuring the brightness of a particular star through a telescope,using different filters in the visual (yellow-green),violet,and ultraviolet regions.What is the name of the technique being used by this astronomer?

Discovering the Night Sky

Gravitation and the Waltz of the Planets

Light and Telescopes

Formation of the Solar System and Other Planetary Systems

Exoplanets

The Terrestrial Planets and Their Moons

The Outer Planets and Their Moons

Vagabonds of the Solar System

The Sun: Our Extraordinary Ordinary Star

The Lives of the Stars From Birth Through Middle Age

The Deaths and Remnants of Stars

The Galaxies

Cosmology

Astrobiology

Filters