Question 1

Nearly all the elements found in nature were formed inside stars, EXCEPT for

Accepted Answer

A)   carbon and silicon.
B)   hydrogen and helium.
C)   helium and carbon.
D)   silver and technetium.
E)   uranium and radium.

Question 2

Can our Sun ever become a nova? Why?

Accepted Answer

No, ours is a single star, wit...

Question 3

Neutron stars and black holes are formed by

Accepted Answer

A)   the star formation process.
B)   mass transfer in binary star systems.
C)   novae.
D)   type I supernovae.
E)   type II supernovae.

Question 4

The remains of type II supernovae (massive star, core collapse supernovae)  are seen in the sky as

Accepted Answer

A)   nebulae that are shrinking as the central mass pulls them in.
B)   nebulae that are expanding at thousands of kilometers per hour.
C)   nebulae that are stellar nurseries.
D)   white dwarfs.
E)   white holes.

Question 5

An iron core cannot support a star because

Accepted Answer

A)   iron is the heaviest element, and sinks upon differentiation.
B)   iron has poor nuclear binding energy.
C)   iron cannot fuse with other nuclei to produce energy.
D)   iron supplies too much pressure.
E)   iron is in the form of a gas, not a solid, in the center of a star.

Question 6

Short duration gamma-ray bursts are explained as the merger of two neutron stars.

Accepted Answer

A) True 
 B)False

Question 7

What is stellar nucleosynthesis?

Accepted Answer

A)   The formation of heavier elements inside stars
B)   The formation of planetary nebulae by red giants
C)   The formation of stars from a nucleus of contracting material
D)   The formation of white dwarfs, neutron stars, and black holes from stars
E)   The process by which stars form interstellar dust

Question 8

Why should the youngest stars be made of the heaviest elements?

Accepted Answer

With each generation of supern...

Question 9

A massive star can fuse only up to the element silicon in its core.

Accepted Answer

A) True 
 B)False

Question 10

Which statement about young stars is FALSE?

Accepted Answer

A)   They contain a larger fraction of heavy elements than previous generations.
B)   They are born in a dustier environment than earlier generations.
C)   They are more likely to have planets forming with them than earlier generations.
D)   The high mass stars will be more likely to produce heavier elements as they evolve.
E)   Being young, they will have more pure hydrogen than earlier generations.

Question 11

Novae are more closely related to type II than to type I supernovae.

Accepted Answer

A) True 
 B)False

Question 12

Astronomers believe that gamma-ray bursters emit radiation equally in all directions.

Accepted Answer

A) True 
 B)False

Question 13

As a star's evolution approaches the Type II supernova, we find

Accepted Answer

A)   the heavier the element, the less time it takes to make it.
B)   the heavier the element, the higher the temperature to fuse it.
C)   helium to carbon fusion takes at least 100 million K to start.
D)   photodisintegration of iron nuclei begins at 10 billion K to ignite the supernova.
E)   All of the above are correct.

Question 14

Type II supernovae have little hydrogen in their spectra; it had been used up already.

Accepted Answer

A) True 
 B)False

Question 15

The vast majority of pulsars are known only from their pulses in

Accepted Answer

A)   X-rays.
B)   gamma-rays.
C)   visible light.
D)   microwaves.
E)   radio waves.

Question 16

An iron core will collapse in approximately one ________ in a type II supernova event.

Accepted Answer

The answer of An iron core will collapse in approximately...

Question 17

Why does conversion of its core to iron have to mark the end of a star's life? Which stars can end up with iron cores?

Accepted Answer

Stars with a total mass of 8 solar masse...

Question 18

What is the importance of 1.4 solar masses in stellar evolution?

Accepted Answer

1.4 solar masses is the Chandrasekhar Li...

Question 19

How does the death of one very massive star give birth to perhaps hundreds of smaller ones soon thereafter?

Accepted Answer

The more massive the star, the faster it...

Question 20

The average density of neutron stars approaches

Accepted Answer

A)   a million times that of normal matter.
B)   a million times that of even a white dwarf.
C)   about 10¹⁷ kg/m³, similar to the density of atomic nuclei.
D)   about 10¹⁸ times that of water.
E)   infinity.

Exam 11: Stellar Explosions

The average density of neutron stars approaches

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Neutron stars and black holes are formed by

Correct AnswerverifiedShow Answer

Can our Sun ever become a nova? Why?

Correct AnswerverifiedNo, ours is a single star, wit...View AnswerShow Answer

Short duration gamma-ray bursts are explained as the merger of two neutron stars.

Correct AnswerverifiedShow Answer

How does the death of one very massive star give birth to perhaps hundreds of smaller ones soon thereafter?

Correct AnswerverifiedThe more massive the star, the faster it...View AnswerShow Answer

What is stellar nucleosynthesis?

Correct AnswerverifiedShow Answer

Why should the youngest stars be made of the heaviest elements?

Correct AnswerverifiedWith each generation of supern...View AnswerShow Answer

Nearly all the elements found in nature were formed inside stars, EXCEPT for

Correct AnswerverifiedShow Answer

Why does conversion of its core to iron have to mark the end of a star's life? Which stars can end up with iron cores?

Correct AnswerverifiedStars with a total mass of 8 solar masse...View AnswerShow Answer

As a star's evolution approaches the Type II supernova, we find

Correct AnswerverifiedShow Answer

An iron core will collapse in approximately one ________ in a type II supernova event.

Correct AnswerverifiedShow Answer

An iron core cannot support a star because

Correct AnswerverifiedShow Answer

The remains of type II supernovae (massive star, core collapse supernovae) are seen in the sky as

Correct AnswerverifiedShow Answer

Astronomers believe that gamma-ray bursters emit radiation equally in all directions.

Correct AnswerverifiedShow Answer

Type II supernovae have little hydrogen in their spectra; it had been used up already.

Correct AnswerverifiedShow Answer

Novae are more closely related to type II than to type I supernovae.

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Which statement about young stars is FALSE?

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What is the importance of 1.4 solar masses in stellar evolution?

Correct Answerverified1.4 solar masses is the Chandrasekhar Li...View AnswerShow Answer

The vast majority of pulsars are known only from their pulses in

Correct AnswerverifiedShow Answer

A massive star can fuse only up to the element silicon in its core.

Correct AnswerverifiedShow Answer

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No, ours is a single star, wit...
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The more massive the star, the faster it...
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With each generation of supern...
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Stars with a total mass of 8 solar masse...
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1.4 solar masses is the Chandrasekhar Li...
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