Question 1

Most pulsars _____.

Accepted Answer

A)  speed up their rotation as they age 
B)  become more luminous as they age 
C)  emit lower energy radiation as they age 
D)  emit higher energy radiation as they age 
E)  slow downtheir rotation as they age 
A)  speed up their rotation as they age 
B)  become more luminous as they age 
C)  emit lower energy radiation as they age 
D)  emit higher energy radiation as they age 
E)  slow downtheir rotation as they age

Question 2

Gamma ray bursts were first recorded while trying to detect _____.

Accepted Answer

A)  solar flares 
B)  the Aurora Borealis 
C)  nuclear reactor accidents 
D)  nuclear tests 
E)  particle accelerator leakage 
A)  solar flares 
B)  the Aurora Borealis 
C)  nuclear reactor accidents 
D)  nuclear tests 
E)  particle accelerator leakage

Question 3

The event horizon of a black hole is the point where _____.

Accepted Answer

A)  the mass of the black hole is concentrated in a singularity 
B)  the accretion disk around the black hole contacts its surface 
C)  the escape velocity equals the speed of light 
D)  tidal forces ionize infalling gas 
E)  an infalling particle reaches equilibrium with radiation pressure 
A)  the mass of the black hole is concentrated in a singularity 
B)  the accretion disk around the black hole contacts its surface 
C)  the escape velocity equals the speed of light 
D)  tidal forces ionize infalling gas 
E)  an infalling particle reaches equilibrium with radiation pressure

Question 4

Pulsars were discovered because they _____.

Accepted Answer

A)  provide the energy to ionize supernova remnants 
B)  radiate gravitational waves 
C)  absorb matter from a binary companion through an accretion disk 
D)  emit short, regular bursts of radiation 
E)  undergo nova eruptions on a regular period of a few years 
A)  provide the energy to ionize supernova remnants 
B)  radiate gravitational waves 
C)  absorb matter from a binary companion through an accretion disk 
D)  emit short, regular bursts of radiation 
E)  undergo nova eruptions on a regular period of a few years

Question 5

The event horizon is located at the Schwarzschild radius.

Accepted Answer

A) True 
 B)False

Question 6

If the Sun was replaced by a black hole of equal mass, Earth would _____.

Accepted Answer

A)  fall into the black hole on a virtually straight path 
B)  spiral in to the black hole over several months 
C)  spiral in to the black hole over the course of several decades 
D)  continue in its normal orbit 
E)  spiral away from the black hole, pushed by gravitational waves 
A)  fall into the black hole on a virtually straight path 
B)  spiral in to the black hole over several months 
C)  spiral in to the black hole over the course of several decades 
D)  continue in its normal orbit 
E)  spiral away from the black hole, pushed by gravitational waves

Question 7

What observational properties of pulsars allowed astronomers to discover them as a new type of object?

Accepted Answer

A pulsar emits a very regular pattern of

Question 8

A neutron star is created when a(n) ___.

Accepted Answer

A)  collapsing stellar core exceeds the Schwarzschild limit 
B)  stellar core ignites iron fusion 
C)  collapsing stellar core exceeds the Chandrasekhar limit 
D)  stellar core exceeds the Roche limit 
E)  collapsing stellar core exceeds the Hawking limit 
A)  collapsing stellar core exceeds the Schwarzschild limit 
B)  stellar core ignites iron fusion 
C)  collapsing stellar core exceeds the Chandrasekhar limit 
D)  stellar core exceeds the Roche limit 
E)  collapsing stellar core exceeds the Hawking limit

Question 9

What evidence did astronomers use to prove jets travel in opposite directions?

Accepted Answer

A)  spectral lines from fast-moving red- and blue-shifted ionized gas 
B)  gamma ray emission spectra 
C)  magnetic tubes in accretion disks 
D)  mass transfer from a binary star to a compact companion 
E)  pulsar rotation periods 
A)  spectral lines from fast-moving red- and blue-shifted ionized gas 
B)  gamma ray emission spectra 
C)  magnetic tubes in accretion disks 
D)  mass transfer from a binary star to a compact companion 
E)  pulsar rotation periods

Question 10

Astronauts approaching a black hole would observe that _____.

Accepted Answer

A)  time appears to slows down for them 
B)  time appears to speed up for external observers 
C)  they become squashed flat - their heads and feet are pushed together by gravitational tides 
D)  they become stretched thin - their heads and feet are pulled apart by gravitational tides 
E)  nothing appears to change 
A)  time appears to slows down for them 
B)  time appears to speed up for external observers 
C)  they become squashed flat - their heads and feet are pushed together by gravitational tides 
D)  they become stretched thin - their heads and feet are pulled apart by gravitational tides 
E)  nothing appears to change

Question 11

The oldest pulsars are billions of years old.

Accepted Answer

A) True 
 B)False

Question 12

Most neutron stars are the remnants of _____ explosions.

Accepted Answer

A)  type II supernovae 
B)  type Ia supernovae 
C)  type Ib supernovae 
D)  novae 
E)  planetary nebulae 
A)  type II supernovae 
B)  type Ia supernovae 
C)  type Ib supernovae 
D)  novae 
E)  planetary nebulae

Question 13

Millisecond pulsars _____.

Accepted Answer

A)  are created in supernova explosions of the most massive stars 
B)  result from the collision of two neutron stars 
C)  represent the youngest pulsars detected 
D)  result from long-term mass transfer from a companion star 
E)  are a theoretical prediction that has not been observed 
A)  are created in supernova explosions of the most massive stars 
B)  result from the collision of two neutron stars 
C)  represent the youngest pulsars detected 
D)  result from long-term mass transfer from a companion star 
E)  are a theoretical prediction that has not been observed

Question 14

In a binary system containing two neutron stars, the objects will ____.

Accepted Answer

A)  radiate orbital energy away as gravitational radiation and move farther apart 
B)  radiate orbital energy away as gravitational radiation and move closer together 
C)  exchange mass until their orbital periods become equal 
D)  exchange mass until they are in synchronous rotation 
E)  exchange angular momentum, lengthening the period of the pulsar 
A)  radiate orbital energy away as gravitational radiation and move farther apart 
B)  radiate orbital energy away as gravitational radiation and move closer together 
C)  exchange mass until their orbital periods become equal 
D)  exchange mass until they are in synchronous rotation 
E)  exchange angular momentum, lengthening the period of the pulsar

Question 15

A magnetar is a type of ____.

Accepted Answer

A)  hypernova 
B)  neutron star 
C)  black hole 
D)  jet 
E)  X-ray burster 
A)  hypernova 
B)  neutron star 
C)  black hole 
D)  jet 
E)  X-ray burster

Question 16

A supermassive, rapidly rotating star may generate a gamma-ray burst in a(n) _______________ eruption.

Accepted Answer

hypernova,

Question 17

Which statement best describes a neutron star's formation as a supernova explodes and the core begins to collapse inward?

Accepted Answer

A)  neutrinos and antineutrinos combine into neutrons 
B)  electrons and protons combine into neutrons and neutrinos 
C)  electrons and protons combine into neutrons and neutrinos. 
D)  electrons and positrons combine into neutrons and neutrinos. 
E)  protons and antiprotons combine into neutrons and neutrinos 
A)  neutrinos and antineutrinos combine into neutrons 
B)  electrons and protons combine into neutrons and neutrinos 
C)  electrons and protons combine into neutrons and neutrinos. 
D)  electrons and positrons combine into neutrons and neutrinos. 
E)  protons and antiprotons combine into neutrons and neutrinos

Question 18

Matter falling onto a compact object, such as a neutron star or black hole,forms a(n):

Accepted Answer

A)  accretion disk 
B)  binary star 
C)  gamma-ray burst 
D)  pulsar 
E)  magnetar 
A)  accretion disk 
B)  binary star 
C)  gamma-ray burst 
D)  pulsar 
E)  magnetar

Question 19

A hypernova is one of several types of events that create a gamma ray burst.

Accepted Answer

A) True 
 B)False

Question 20

A pulsar emits bursts of radio photons.

Accepted Answer

A) True 
 B)False

Exam 14: Neutron Stars and Black Holes

Most pulsars _____.

Gamma ray bursts were first recorded while trying to detect _____.

The event horizon of a black hole is the point where _____.

Pulsars were discovered because they _____.

The event horizon is located at the Schwarzschild radius.

If the Sun was replaced by a black hole of equal mass, Earth would _____.

What observational properties of pulsars allowed astronomers to discover them as a new type of object?

A neutron star is created when a(n) ___.

What evidence did astronomers use to prove jets travel in opposite directions?

Astronauts approaching a black hole would observe that _____.

The oldest pulsars are billions of years old.

Most neutron stars are the remnants of _____ explosions.

Millisecond pulsars _____.

In a binary system containing two neutron stars, the objects will ____.

A magnetar is a type of ____.

A supermassive, rapidly rotating star may generate a gamma-ray burst in a(n) _______________ eruption.

Which statement best describes a neutron star's formation as a supernova explodes and the core begins to collapse inward?

Matter falling onto a compact object, such as a neutron star or black hole,forms a(n):

A hypernova is one of several types of events that create a gamma ray burst.

A pulsar emits bursts of radio photons.

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Origins of Modern Astronomy

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Origin of the Solar System and Extrasolar Planets

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