Question 1

Which is brighter in our sky,a star with apparent magnitude 2 or a star with apparent magnitude 7? By how much is the star brighter?

Accepted Answer

A star with apparent magnitude 2 is 100 ...

Question 2

A star of spectral type O lives approximately how long on the main sequence?

Accepted Answer

A)  1,000 years
B)  10,000 years
C)  10 million years
D)  100 million years
E)  1 billion years

Question 3

Process of Science: Why is the classification of stellar spectral types not in alphabetical order?

Accepted Answer

Stars were first classified empirically,...

Question 4

Which of the following statements about spectral types of stars is not generally true?

Accepted Answer

A)  The spectral type of a star can be used to determine its surface temperature.
B)  The spectral type of a star can be used to determine its distance.
C)  The spectral type of a star can be used to determine its color.
D)  The spectral type of a star can be determined by identifying lines in its spectrum.

Question 5

The following questions refer to the sketch of the H-R diagram below.Please choose the best answer in each case,i.e. ,choice (a)refers to the entire main sequence,while (c)and (d)refer to only small parts of the main sequence.If choice (c)or (d)offers a better answer to a particular question than (a),use the best choice.You may use the same choice more than once.
 
-Which group represents stars that have no nuclear fusion in their cores?

Accepted Answer

The answer of The following questions refer to the sketch...

Question 6

The sketch below shows groups of stars on the H-R diagram labeled (a) through (e) .Note that (a) represents the entire main sequence while (c) and (d) represent only small parts of the main sequence.
 
-Which group represents stars of the largest radii?

Accepted Answer

A)  A
B)  B
C)  C
D)  D
E)  E

Question 7

What is the approximate chemical composition (by mass) with which all stars are born?

Accepted Answer

A)  three quarters hydrogen,one quarter helium,no more than 2% heavier elements
B)  half hydrogen and half helium
C)  98% hydrogen,2% helium
D)  95% hydrogen,4% helium,no more than 1% heavier elements

Question 8

Two stars,Fred and Barney,are of the same size.Fred has spectral type F,while Barney has spectral type B.Which one is more luminous?

Accepted Answer

Barney has a hotter surface te...

Question 9

Two stars,Tom and Jerry,have the same spectral type.Tom is luminosity class V and Jerry is luminosity class I.Which star is bigger? Which star is more luminous? Which star has a hotter surface temperature? Explain your answers.

Accepted Answer

Tom is on the main sequence,while Jerry ...

Question 10

Where do we find our star on the H-R diagram?

Accepted Answer

A)  In the middle of the main sequence
B)  On the far left of the main sequence
C)  With the red giants
D)  On the lower left

Question 11

Some stars are cool enough to have molecules in their atmosphere.

Accepted Answer

A) True 
 B)False

Question 12

On a Hertzsprung-Russell diagram,where would we find stars that are cool and dim?

Accepted Answer

A)  upper right
B)  lower right
C)  upper left
D)  lower left

Question 13

The total amount of power (in watts,for example) that a star radiates into space is called its

Accepted Answer

A)  apparent brightness.
B)  absolute magnitude.
C)  luminosity.
D)  flux.

Question 14

To calculate the masses of stars in a binary system,we must measure their

Accepted Answer

A)  spectral types and distance from Earth.
B)  absolute magnitudes and luminosities.
C)  luminosities and distance from Earth.
D)  orbital period and average orbital distance.

Question 15

Which of the following statements about spectral types of stars is true?

Accepted Answer

A)  The spectral type of a star can be used to determine its surface temperature.
B)  The spectral type of a star can be used to determine its color.
C)  A star with spectral type A is cooler than a star with spectral type B.
D)  A star with spectral type F2 is hotter than a star with spectral type F3.
E)  All of the above are true.

Question 16

The spectral sequence in order of decreasing temperature is

Accepted Answer

A)  OFBAGKM.
B)  OBAGFKM.
C)  OBAFGKM.
D)  ABFGKMO.
E)  BAGFKMO.

Question 17

Massive,more luminous stars have shorter lives than their smaller,dimmer counterparts.

Accepted Answer

A) True 
 B)False

Question 18

Refer to the choices in the table for the following questions.
 
-Which star looks reddest in color?

Accepted Answer

The answer of Refer to the choices in the table...

Question 19

What is the common trait of all main-sequence stars?

Accepted Answer

A)  They are in the final stage of their lives.
B)  They generate energy through hydrogen fusion in their core.
C)  They are all spectral type G.
D)  They all have approximately the same mass.

Question 20

Which has a greater luminosity,a star with absolute magnitude +4 or a star with absolute magnitude -6? By how much is it brighter?

Accepted Answer

A star with absolute magnitude -6 is int...

Exam 15: Surveying the Stars

Which has a greater luminosity,a star with absolute magnitude +4 or a star with absolute magnitude -6? By how much is it brighter?

Correct Answer
verified
A star with absolute magnitude -6 is int...
View Answer

Refer to the choices in the table for the following questions. -Which star looks reddest in color?

Correct Answer
verified

The total amount of power (in watts,for example) that a star radiates into space is called its

Correct Answer
verified

What is the approximate chemical composition (by mass) with which all stars are born?

Correct Answer
verified

The spectral sequence in order of decreasing temperature is

Correct Answer
verified

The sketch below shows groups of stars on the H-R diagram labeled (a) through (e) .Note that (a) represents the entire main sequence while (c) and (d) represent only small parts of the main sequence. -Which group represents stars of the largest radii?

Correct Answer
verified

A star of spectral type O lives approximately how long on the main sequence?

Correct Answer
verified

Which is brighter in our sky,a star with apparent magnitude 2 or a star with apparent magnitude 7? By how much is the star brighter?

Correct Answer
verified
A star with apparent magnitude 2 is 100 ...
View Answer

Where do we find our star on the H-R diagram?

Correct Answer
verified

Process of Science: Why is the classification of stellar spectral types not in alphabetical order?

Correct Answer
verified
Stars were first classified empirically,...
View Answer

Some stars are cool enough to have molecules in their atmosphere.

Correct Answer
verified

What is the common trait of all main-sequence stars?

Correct Answer
verified

To calculate the masses of stars in a binary system,we must measure their

Correct Answer
verified

Massive,more luminous stars have shorter lives than their smaller,dimmer counterparts.

Correct Answer
verified

Two stars,Tom and Jerry,have the same spectral type.Tom is luminosity class V and Jerry is luminosity class I.Which star is bigger? Which star is more luminous? Which star has a hotter surface temperature? Explain your answers.

Correct Answer
verified
Tom is on the main sequence,while Jerry ...
View Answer

Correct Answer
verified

Which of the following statements about spectral types of stars is not generally true?

Correct Answer
verified

On a Hertzsprung-Russell diagram,where would we find stars that are cool and dim?

Correct Answer
verified

Which of the following statements about spectral types of stars is true?

Correct Answer
verified

Two stars,Fred and Barney,are of the same size.Fred has spectral type F,while Barney has spectral type B.Which one is more luminous?

Correct Answer
verified
Barney has a hotter surface te...
View Answer

Exam 15: Surveying the Stars

Which has a greater luminosity,a star with absolute magnitude +4 or a star with absolute magnitude -6? By how much is it brighter?

Correct AnswerverifiedA star with absolute magnitude -6 is int...View AnswerShow Answer

Refer to the choices in the table for the following questions. -Which star looks reddest in color?

Correct AnswerverifiedShow Answer

The total amount of power (in watts,for example) that a star radiates into space is called its

Correct AnswerverifiedShow Answer

What is the approximate chemical composition (by mass) with which all stars are born?

Correct AnswerverifiedShow Answer

The spectral sequence in order of decreasing temperature is

Correct AnswerverifiedShow Answer

The sketch below shows groups of stars on the H-R diagram labeled (a) through (e) .Note that (a) represents the entire main sequence while (c) and (d) represent only small parts of the main sequence. -Which group represents stars of the largest radii?

Correct AnswerverifiedShow Answer

A star of spectral type O lives approximately how long on the main sequence?

Correct AnswerverifiedShow Answer

Which is brighter in our sky,a star with apparent magnitude 2 or a star with apparent magnitude 7? By how much is the star brighter?

Correct AnswerverifiedA star with apparent magnitude 2 is 100 ...View AnswerShow Answer

Where do we find our star on the H-R diagram?

Correct AnswerverifiedShow Answer

Process of Science: Why is the classification of stellar spectral types not in alphabetical order?

Correct AnswerverifiedStars were first classified empirically,...View AnswerShow Answer

Some stars are cool enough to have molecules in their atmosphere.

Correct AnswerverifiedShow Answer

What is the common trait of all main-sequence stars?

Correct AnswerverifiedShow Answer

To calculate the masses of stars in a binary system,we must measure their

Correct AnswerverifiedShow Answer

Massive,more luminous stars have shorter lives than their smaller,dimmer counterparts.

Correct AnswerverifiedShow Answer

Two stars,Tom and Jerry,have the same spectral type.Tom is luminosity class V and Jerry is luminosity class I.Which star is bigger? Which star is more luminous? Which star has a hotter surface temperature? Explain your answers.

Correct AnswerverifiedTom is on the main sequence,while Jerry ...View AnswerShow Answer

Correct AnswerverifiedShow Answer

Which of the following statements about spectral types of stars is not generally true?

Correct AnswerverifiedShow Answer

On a Hertzsprung-Russell diagram,where would we find stars that are cool and dim?

Correct AnswerverifiedShow Answer

Which of the following statements about spectral types of stars is true?

Correct AnswerverifiedShow Answer

Two stars,Fred and Barney,are of the same size.Fred has spectral type F,while Barney has spectral type B.Which one is more luminous?

Correct AnswerverifiedBarney has a hotter surface te...View AnswerShow Answer

Correct Answer
verified
A star with absolute magnitude -6 is int...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
A star with apparent magnitude 2 is 100 ...
View Answer

Correct Answer
verified

Correct Answer
verified
Stars were first classified empirically,...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Tom is on the main sequence,while Jerry ...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Barney has a hotter surface te...
View Answer