Question 1

The one property of a main-sequence star that determines all its other properties is its:

Accepted Answer

A) luminosity 
B) mass 
C) temperature 
D) spectral type 
E) brightness 
A) luminosity 
B) mass 
C) temperature 
D) spectral type 
E) brightness

Question 2

The stars that have the largest radii are classified as supergiants.

Accepted Answer

A) True 
 B)False

Question 3

The Hertzsprung-Russell diagram is a graph of _________ for stars.

Accepted Answer

A) mass versus brightness 
B) size versus mass 
C) luminosity versus temperature 
D) mass versus spectral type 
E) luminosity versus brightness 
A) mass versus brightness 
B) size versus mass 
C) luminosity versus temperature 
D) mass versus spectral type 
E) luminosity versus brightness

Question 4

On a typical H-R diagram,where are the stars with the largest radii located?

Accepted Answer

A) in the upper left corner 
B) in the upper right corner 
C) in the center 
D) in the lower left corner 
E) in the lower right corner 
A) in the upper left corner 
B) in the upper right corner 
C) in the center 
D) in the lower left corner 
E) in the lower right corner

Question 5

The star named Capella has an apparent magnitude of 0,while the star named Polaris has an apparent magnitude of 2,which means that Capella is _________ than Polaris.

Accepted Answer

A) 18 times fainter 
B) 6 times fainter 
C) 2 times fainter 
D) 2 times brighter 
E) 6 times brighter 
A) 18 times fainter 
B) 6 times fainter 
C) 2 times fainter 
D) 2 times brighter 
E) 6 times brighter

Question 6

Imagine you are observing a nearby star.You know that it is a main-sequence star but don't know anything else about it.If you had access to any telescope equipment you wanted,explain how you would determine this star's temperature,luminosity,distance,and radius.

Accepted Answer

You could measure the temperature either

Question 7

Astronomers can measure the speed of the stars in a binary system by measuring the _________ of the stars.

Accepted Answer

A) temperatures 
B) luminosities 
C) distance 
D) colors 
E) spectra 
A) temperatures 
B) luminosities 
C) distance 
D) colors 
E) spectra

Question 8

Eclipsing binary systems:

Accepted Answer

A) orbit in the plane of the sky 
B) exhibit large radial velocity shifts 
C) contain equal mass stars 
D) contain stars that pass in front of one another during their orbit 
E) contain stars that can be resolved as two separate stars 
A) orbit in the plane of the sky 
B) exhibit large radial velocity shifts 
C) contain equal mass stars 
D) contain stars that pass in front of one another during their orbit 
E) contain stars that can be resolved as two separate stars

Question 9

If we know the temperature and luminosity of a star,we can also calculate its:

Accepted Answer

A) radius 
B) mass 
C) chemical composition 
D) brightness 
E) all of the above 
A) radius 
B) mass 
C) chemical composition 
D) brightness 
E) all of the above

Question 10

How many arcseconds are there in 1 degree?

Accepted Answer

A) 60 
B) 360 
C) 3,600 
D) 6,000 
E) 36,000 
A) 60 
B) 360 
C) 3,600 
D) 6,000 
E) 36,000

Question 11

A star's mass determines where it lies on the main sequence of an H-R diagram.

Accepted Answer

A) True 
 B)False

Question 12

If a star's parallax is measured using identical telescopes,one on Earth and the other on Mars,which planet's telescope would measure the biggest parallax? Explain your answer.

Accepted Answer

The telescope on Mars would measure a la

Question 13

Star A is exactly the same color as star B and appears equally bright.Through stellar parallax measurements,we find that star B is twice as far away from us as star A.Determine which star has the largest radius and how much larger it is.

Accepted Answer

For stars of equal brightness,luminosity

Question 14

Star E is the same temperature as star F,but star E is four times as luminous as star F.How do the radii of the stars compare?

Accepted Answer

A) Star E has twice the radius of star F. 
B) Star E has four times the radius of star F. 
C) Star F has twice the radius of star E. 
D) Star F has four times the radius of star E. 
E) They are the same size. 
A) Star E has twice the radius of star F. 
B) Star E has four times the radius of star F. 
C) Star F has twice the radius of star E. 
D) Star F has four times the radius of star E. 
E) They are the same size.

Question 15

What spectral class is the Sun?

Accepted Answer

A) A0 
B) B7 
C) F5 
D) M3 
E) G2 
A) A0 
B) B7 
C) F5 
D) M3 
E) G2

Question 16

The absolute magnitude of a star is a measure of its luminosity.

Accepted Answer

A) True 
 B)False

Question 17

Spectra of the least massive main-sequence stars show the largest amount of absorption from molecules like TiO and CN.

Accepted Answer

A) True 
 B)False

Question 18

Star A is a red star.Star B is a blue star.Which star is hotter?

Accepted Answer

A) Star A is hotter. 
B) Star B is hotter. 
C) They are the same temperature. 
D) We also need to know the luminosities of the stars to determine their temperatures. 
E) Color is not related to temperature at all. 
A) Star A is hotter. 
B) Star B is hotter. 
C) They are the same temperature. 
D) We also need to know the luminosities of the stars to determine their temperatures. 
E) Color is not related to temperature at all.

Question 19

Stars are made mostly of:

Accepted Answer

A) helium 
B) oxygen 
C) hydrogen 
D) nitrogen 
E) carbon 
A) helium 
B) oxygen 
C) hydrogen 
D) nitrogen 
E) carbon

Question 20

Star A and star B both have the same temperature but different sizes and distances.As a result,star A is more luminous than star B,but star B is brighter than star A.Which of these statements about the absolute and apparent magnitudes of the two stars is correct?

Accepted Answer

A) Star A has a larger apparent magnitude and a larger absolute magnitude. 
B) Star A has a larger apparent magnitude,while star B has a larger absolute magnitude. 
C) Star B has a larger apparent magnitude and a larger absolute magnitude. 
D) Star B has a larger apparent magnitude,while star A has a larger absolute magnitude. 
E) Both stars have the same apparent and absolute magnitudes. 
A) Star A has a larger apparent magnitude and a larger absolute magnitude. 
B) Star A has a larger apparent magnitude,while star B has a larger absolute magnitude. 
C) Star B has a larger apparent magnitude and a larger absolute magnitude. 
D) Star B has a larger apparent magnitude,while star A has a larger absolute magnitude. 
E) Both stars have the same apparent and absolute magnitudes.

Exam 13: Taking the Measure of Stars

The one property of a main-sequence star that determines all its other properties is its:

The stars that have the largest radii are classified as supergiants.

The Hertzsprung-Russell diagram is a graph of _________ for stars.

On a typical H-R diagram,where are the stars with the largest radii located?

The star named Capella has an apparent magnitude of 0,while the star named Polaris has an apparent magnitude of 2,which means that Capella is _________ than Polaris.

Imagine you are observing a nearby star.You know that it is a main-sequence star but don't know anything else about it.If you had access to any telescope equipment you wanted,explain how you would determine this star's temperature,luminosity,distance,and radius.

Astronomers can measure the speed of the stars in a binary system by measuring the _________ of the stars.

Eclipsing binary systems:

If we know the temperature and luminosity of a star,we can also calculate its:

How many arcseconds are there in 1 degree?

A star's mass determines where it lies on the main sequence of an H-R diagram.

If a star's parallax is measured using identical telescopes,one on Earth and the other on Mars,which planet's telescope would measure the biggest parallax? Explain your answer.

Star A is exactly the same color as star B and appears equally bright.Through stellar parallax measurements,we find that star B is twice as far away from us as star A.Determine which star has the largest radius and how much larger it is.

Star E is the same temperature as star F,but star E is four times as luminous as star F.How do the radii of the stars compare?

What spectral class is the Sun?

The absolute magnitude of a star is a measure of its luminosity.

Spectra of the least massive main-sequence stars show the largest amount of absorption from molecules like TiO and CN.

Star A is a red star.Star B is a blue star.Which star is hotter?

Stars are made mostly of:

Star A and star B both have the same temperature but different sizes and distances.As a result,star A is more luminous than star B,but star B is brighter than star A.Which of these statements about the absolute and apparent magnitudes of the two stars is correct?

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 Adornments Moons and Rings

Dwarf Planets and Small Solar System Bodies

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-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

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