Question 1

How do astronomers know that the newly found L and T spectral types represent objects cooler than M spectral class?

Accepted Answer

L star spectra contain bands produced by

Question 2

Which of the following kinds of stars best obey the mass-luminosity relation?

Accepted Answer

A)  main-sequence stars 
B)  giant stars 
C)  supergiant stars 
D)  white dwarfs 
E)  All of the other choices are correct. 
A)  main-sequence stars 
B)  giant stars 
C)  supergiant stars 
D)  white dwarfs 
E)  All of the other choices are correct.

Question 3

_____ spectral type stars are hotter than _____ spectral type stars.

Accepted Answer

A)  A, K 
B)  M, F 
C)  B, O 
D)  L, G 
A)  A, K 
B)  M, F 
C)  B, O 
D)  L, G

Question 4

In the light curve below, what is the period of the eclipsing binary?

Accepted Answer

A)  5 days 
B)  32.5 days 
C)  7.5 days 
D)  42.5 days 
E)  50 days 
A)  5 days 
B)  32.5 days 
C)  7.5 days 
D)  42.5 days 
E)  50 days

Question 5

-Table 8-1 Use the chart below to answer the following question(s).
From the data given, which star in Table 8-1 has the greatest luminosity?

Accepted Answer

A)  65 Tau 
B)  HR 4621 
C)  α Pic 
D)  58 Ori 
E)  HR 2491 
A)  65 Tau 
B)  HR 4621 
C)  α Pic 
D)  58 Ori 
E)  HR 2491

Question 6

The parallax of the star 75 Leo is 0.10 and its apparent visual magnitude is +5.18. The absolute visual magnitude of 75 Leo is ____________________.

Accepted Answer

The answer of The parallax of the star 75 Leo...

Question 7

Arcturus has an m V = -0.04 and M V = -0.3. Its distance is 10-3.4 pc.

Accepted Answer

A) True 
 B)False

Question 8

A star's apparent magnitude is a measure of

Accepted Answer

A)  how bright it appears to us if it is at its actual distance. 
B)  how bright it appears to us at a standard distance of 10 pc. 
C)  its energy output per second compared to the Sun. 
D)  its mass in solar masses. 
E)  its surface temperature in Kelvin. 
A)  how bright it appears to us if it is at its actual distance. 
B)  how bright it appears to us at a standard distance of 10 pc. 
C)  its energy output per second compared to the Sun. 
D)  its mass in solar masses. 
E)  its surface temperature in Kelvin.

Question 9

The star HR 4621 has an apparent magnitude of 2.6 and an absolute magnitude of -0.3. This star is at a distance

Accepted Answer

A)  closer than 10 pc. 
B)  farther than 10 pc. 
C)  No way to tell. 
A)  closer than 10 pc. 
B)  farther than 10 pc. 
C)  No way to tell.

Question 10

The total mass of a binary system can be calculated from

Accepted Answer

A)  the ratio of the angular separation from the center of mass of each of the stars. 
B)  the distance to the binary and its radial velocity. 
C)  the semimajor axis and period of the orbit. 
D)  the radial velocities of the two stars. 
E)  the time required for the smaller star to eclipse the larger star. 
A)  the ratio of the angular separation from the center of mass of each of the stars. 
B)  the distance to the binary and its radial velocity. 
C)  the semimajor axis and period of the orbit. 
D)  the radial velocities of the two stars. 
E)  the time required for the smaller star to eclipse the larger star.

Question 11

Two stars of the same spectral class must have the same

Accepted Answer

A)  radius. 
B)  temperature. 
C)  mass. 
D)  distance. 
E)  all of the other choices. 
A)  radius. 
B)  temperature. 
C)  mass. 
D)  distance. 
E)  all of the other choices.

Question 12

Why don't we see hydrogen Balmer lines in the spectra of stars with temperatures of 45,000 K?

Accepted Answer

A)  There is no hydrogen in stars this hot. 
B)  The stars are hot enough that most of the hydrogen is ionized and the atoms cannot absorb energy. 
C)  These stars are so cool that nearly all of the electrons in the hydrogen atom are in the ground state. 
D)  Stars of this temperature are too cool to produce an absorption spectrum. 
E)  Stars of this temperature are too hot to produce an absorption spectrum. 
A)  There is no hydrogen in stars this hot. 
B)  The stars are hot enough that most of the hydrogen is ionized and the atoms cannot absorb energy. 
C)  These stars are so cool that nearly all of the electrons in the hydrogen atom are in the ground state. 
D)  Stars of this temperature are too cool to produce an absorption spectrum. 
E)  Stars of this temperature are too hot to produce an absorption spectrum.

Question 13

According to the text, humans have a _____ size compared to stellar and microscopic objects.

Accepted Answer

A)  extra small 
B)  small 
C)  medium 
D)  large 
A)  extra small 
B)  small 
C)  medium 
D)  large

Question 14

The spectral types for each of five stars are given. Which star in would have the greatest surface temperature?

Accepted Answer

A)  α For; F8 
B)  ο Cet; M7 
C)  35 Ari; B3 
D)  γ Tri; A0 
E)  ξ Per; O7 
A)  α For; F8 
B)  ο Cet; M7 
C)  35 Ari; B3 
D)  γ Tri; A0 
E)  ξ Per; O7

Question 15

The masses and diameters of each star in a binary can be determined from ____________________ binaries.

Accepted Answer

The answer of The masses and diameters of each star...

Question 16

White dwarfs are dense, cool, and dim.

Accepted Answer

A) True 
 B)False

Question 17

Giant stars are members of luminosity class III.

Accepted Answer

A) True 
 B)False

Question 18

The ________ of a star is a measure of the total energy radiated by the star in one second.

Accepted Answer

A)  color 
B)  apparent visual magnitude 
C)  luminosity class 
D)  spectral type 
E)  luminosity 
A)  color 
B)  apparent visual magnitude 
C)  luminosity class 
D)  spectral type 
E)  luminosity

Question 19

Hydrogen lines are weak in the spectra of hot stars because many of the hydrogen atoms have their electrons in levels above the second level.

Accepted Answer

A) True 
 B)False

Question 20

-Table 8-2 Use the chart below to answer the following question(s).
Which star in Table 8-2 has the greatest surface temperature?

Accepted Answer

A)  δ Cen 
B)  HR 4607 
C)  HR 4758 
D)  HD 39801 
E)  9 CMa 
A)  δ Cen 
B)  HR 4607 
C)  HR 4758 
D)  HD 39801 
E)  9 CMa

How do astronomers know that the newly found L and T spectral types represent objects cooler than M spectral class?

Which of the following kinds of stars best obey the mass-luminosity relation?

_ spectral type stars are hotter than _ spectral type stars.

In the light curve below, what is the period of the eclipsing binary?

-Table 8-1 Use the chart below to answer the following question(s). From the data given, which star in Table 8-1 has the greatest luminosity?

The parallax of the star 75 Leo is 0.10 and its apparent visual magnitude is +5.18. The absolute visual magnitude of 75 Leo is ____________________.

Arcturus has an m _V = -0.04 and M _V = -0.3. Its distance is 10^-3.4 pc.

A star's apparent magnitude is a measure of

The star HR 4621 has an apparent magnitude of 2.6 and an absolute magnitude of -0.3. This star is at a distance

The total mass of a binary system can be calculated from

Two stars of the same spectral class must have the same

Why don't we see hydrogen Balmer lines in the spectra of stars with temperatures of 45,000 K?

According to the text, humans have a _____ size compared to stellar and microscopic objects.

The spectral types for each of five stars are given. Which star in would have the greatest surface temperature?

The masses and diameters of each star in a binary can be determined from ____________________ binaries.

White dwarfs are dense, cool, and dim.

Giant stars are members of luminosity class III.

The ________ of a star is a measure of the total energy radiated by the star in one second.

Hydrogen lines are weak in the spectra of hot stars because many of the hydrogen atoms have their electrons in levels above the second level.

-Table 8-2 Use the chart below to answer the following question(s). Which star in Table 8-2 has the greatest surface temperature?

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Formation and Structure of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

Origin of the Solar System and Extrasolar Planets

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus, and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Exam 8: The Family of Stars

How do astronomers know that the newly found L and T spectral types represent objects cooler than M spectral class?

Which of the following kinds of stars best obey the mass-luminosity relation?

_____ spectral type stars are hotter than _____ spectral type stars.

In the light curve below, what is the period of the eclipsing binary?

-Table 8-1 Use the chart below to answer the following question(s). From the data given, which star in Table 8-1 has the greatest luminosity?

The parallax of the star 75 Leo is 0.10 and its apparent visual magnitude is +5.18. The absolute visual magnitude of 75 Leo is ____________________.

Arcturus has an m V = -0.04 and M V = -0.3. Its distance is 10-3.4 pc.

A star's apparent magnitude is a measure of

The star HR 4621 has an apparent magnitude of 2.6 and an absolute magnitude of -0.3. This star is at a distance

The total mass of a binary system can be calculated from

Two stars of the same spectral class must have the same

Why don't we see hydrogen Balmer lines in the spectra of stars with temperatures of 45,000 K?

According to the text, humans have a _____ size compared to stellar and microscopic objects.

The spectral types for each of five stars are given. Which star in would have the greatest surface temperature?

The masses and diameters of each star in a binary can be determined from ____________________ binaries.

White dwarfs are dense, cool, and dim.

Giant stars are members of luminosity class III.

The ________ of a star is a measure of the total energy radiated by the star in one second.

Hydrogen lines are weak in the spectra of hot stars because many of the hydrogen atoms have their electrons in levels above the second level.

-Table 8-2 Use the chart below to answer the following question(s). Which star in Table 8-2 has the greatest surface temperature?

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Formation and Structure of Stars

The Deaths of Stars

Neutron Stars and Black Holes

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

Origin of the Solar System and Extrasolar Planets

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus, and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

_ spectral type stars are hotter than _ spectral type stars.

Arcturus has an m _V = -0.04 and M _V = -0.3. Its distance is 10^-3.4 pc.