Question 1

Gravity is nothing more than a curvature in the fabric of spacetime.

Accepted Answer

A) True 
 B)False

Question 2

Normally muons created by cosmic rays at high altitudes decay in a very short time,a time so short that they should not reach the ground.From the figure below,why does increasing speed of muons created by cosmic rays at high altitudes mean that additional muons will reach the ground before decaying?

Accepted Answer

A faster speed for a muon tran

Question 3

An iron core cannot support a massive main-sequence star because:

Accepted Answer

A)  iron has poor nuclear binding energy 
B)  iron cannot fuse with other nuclei to produce energy 
C)  iron supplies too much pressure 
D)  iron fusion only occurs in a degenerate core 
A)  iron has poor nuclear binding energy 
B)  iron cannot fuse with other nuclei to produce energy 
C)  iron supplies too much pressure 
D)  iron fusion only occurs in a degenerate core

Question 4

A Cepheid star varies in luminosity because:

Accepted Answer

A)  the entire star pulsates from its core to its surface 
B)  the outer envelope of the star pulsates 
C)  the star rotates too quickly 
D)  the star is too massive to be stable 
A)  the entire star pulsates from its core to its surface 
B)  the outer envelope of the star pulsates 
C)  the star rotates too quickly 
D)  the star is too massive to be stable

Question 5

Neutron stars have masses that range from:

Accepted Answer

A)  3.5 M$\bigodot$ to 25 M$\bigodot$ 
B)  1.2 M$\bigodot$ to 30 M$\bigodot$ 
C)  2.5 M$\bigodot$ to 10 M$\bigodot$ 
D)  1.4 M$\bigodot$ to 3 M$\bigodot$ 
A)  3.5 M$\bigodot$ to 25 M$\bigodot$ 
B)  1.2 M$\bigodot$ to 30 M$\bigodot$ 
C)  2.5 M$\bigodot$ to 10 M$\bigodot$ 
D)  1.4 M$\bigodot$ to 3 M$\bigodot$

Question 6

If the Earth were to be condensed down in size until it became a black hole,its Schwarzschild radius would be:

Accepted Answer

A)  1 cm 
B)  1 m 
C)  1 km 
D)  10 km 
A)  1 cm 
B)  1 m 
C)  1 km 
D)  10 km

Question 7

__________ is the result of mass distorting the fabric of spacetime.

Accepted Answer

A)  Energy 
B)  Radiation 
C)  Fusion 
D)  Gravity 
A)  Energy 
B)  Radiation 
C)  Fusion 
D)  Gravity

Question 8

An indestructible robot would feel __________ as it crossed the event horizon of a black hole.

Accepted Answer

A)  incredibly strong tidal forces 
B)  intense heating 
C)  intense gravitational stretching 
D)  nothing 
A)  incredibly strong tidal forces 
B)  intense heating 
C)  intense gravitational stretching 
D)  nothing

Question 9

The densest state of matter found in nature occurs inside a white dwarf star.

Accepted Answer

A) True 
 B)False

Question 10

During the main-sequence evolution of a massive star,increasingly heavier elements are fused in the core,giving the core support for:

Accepted Answer

A)  decreasingly shorter times 
B)  increasingly longer times 
C)  an approximately equal amount of time 
D)  approximately 10,000 years 
A)  decreasingly shorter times 
B)  increasingly longer times 
C)  an approximately equal amount of time 
D)  approximately 10,000 years

Question 11

Once carbon begins burning in the core of a high-mass star,the outer layers begin to fall inward,driving up the fusion rates and speeding up the star's evolution primarily because:

Accepted Answer

A)  the number of particles in the core is decreasing which now take up less space 
B)  most of the energy is now carried away from the core by escaping neutrinos which have few if any obstacles to leaving the star 
C)  carbon is a more stable element that appears to settle the star 
D)  the light given off by the fusion of carbon is a different wavelength than given off by previous reactions so the radiation pressure is much smaller 
A)  the number of particles in the core is decreasing which now take up less space 
B)  most of the energy is now carried away from the core by escaping neutrinos which have few if any obstacles to leaving the star 
C)  carbon is a more stable element that appears to settle the star 
D)  the light given off by the fusion of carbon is a different wavelength than given off by previous reactions so the radiation pressure is much smaller

Question 12

Hawking radiation is emitted by a black hole when:

Accepted Answer

A)  the black hole rotates quickly 
B)  the black hole accretes material 
C)  a virtual pair of particles is created from the vacuum of space 
D)  synchrotron radiation is emitted by infalling charged particles 
A)  the black hole rotates quickly 
B)  the black hole accretes material 
C)  a virtual pair of particles is created from the vacuum of space 
D)  synchrotron radiation is emitted by infalling charged particles

Question 13

Gravitational lensing allows us to see distant objects that would otherwise be blocked by a star or galaxy.

Accepted Answer

A) True 
 B)False

Question 14

What are some ways that finding a Cepheid variable star is significant?

Accepted Answer

First,Cepheid variables are very bright

Question 15

The production of large numbers of neutrons in nuclear reactions at the core of a massive star helps rob the core of energy and speeds its eventual collapse.

Accepted Answer

A) True 
 B)False

Question 16

Which of the following is NOT a common characteristic of a neutron star?

Accepted Answer

A)  Extremely high density 
B)  Enormous magnetic field 
C)  Very short rotation period 
D)  All of these are common characteristics of a neutron star. 
A)  Extremely high density 
B)  Enormous magnetic field 
C)  Very short rotation period 
D)  All of these are common characteristics of a neutron star.

Question 17

The main difference between Cepheid variable stars and RR Lyrae stars is:

Accepted Answer

A)  their pulsation mechanisms 
B)  their masses 
C)  that Cepheids form at much greater distances from Earth 
D)  that RR Lyrae were discovered much earlier than Cepheids 
A)  their pulsation mechanisms 
B)  their masses 
C)  that Cepheids form at much greater distances from Earth 
D)  that RR Lyrae were discovered much earlier than Cepheids

Question 18

Special relativity says that moving clocks run slower.

Accepted Answer

A) True 
 B)False

Question 19

Which has a smaller radius,a 2 M$\bigodot$ neutron star or a 3 M$\bigodot$ neutron star? What supports each of these stars from collapsing to form a black hole?

Accepted Answer

The pressure from degenerate neutrons su

Question 20

Black holes emit no light whatsoever.

Accepted Answer

A) True 
 B)False

Gravity is nothing more than a curvature in the fabric of spacetime.

Normally muons created by cosmic rays at high altitudes decay in a very short time,a time so short that they should not reach the ground.From the figure below,why does increasing speed of muons created by cosmic rays at high altitudes mean that additional muons will reach the ground before decaying?

An iron core cannot support a massive main-sequence star because:

A Cepheid star varies in luminosity because:

Neutron stars have masses that range from:

If the Earth were to be condensed down in size until it became a black hole,its Schwarzschild radius would be:

__________ is the result of mass distorting the fabric of spacetime.

An indestructible robot would feel __________ as it crossed the event horizon of a black hole.

The densest state of matter found in nature occurs inside a white dwarf star.

During the main-sequence evolution of a massive star,increasingly heavier elements are fused in the core,giving the core support for:

Once carbon begins burning in the core of a high-mass star,the outer layers begin to fall inward,driving up the fusion rates and speeding up the star's evolution primarily because:

Hawking radiation is emitted by a black hole when:

Gravitational lensing allows us to see distant objects that would otherwise be blocked by a star or galaxy.

What are some ways that finding a Cepheid variable star is significant?

The production of large numbers of neutrons in nuclear reactions at the core of a massive star helps rob the core of energy and speeds its eventual collapse.

Which of the following is NOT a common characteristic of a neutron star?

The main difference between Cepheid variable stars and RR Lyrae stars is:

Special relativity says that moving clocks run slower.

Which has a smaller radius,a 2 M_$\bigodot$ neutron star or a 3 M_$\bigodot$ neutron star? What supports each of these stars from collapsing to form a black hole?

Black holes emit no light whatsoever.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of Low-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Exam 13: Evolution of High-Mass Stars

Gravity is nothing more than a curvature in the fabric of spacetime.

An iron core cannot support a massive main-sequence star because:

A Cepheid star varies in luminosity because:

Neutron stars have masses that range from:

If the Earth were to be condensed down in size until it became a black hole,its Schwarzschild radius would be:

__________ is the result of mass distorting the fabric of spacetime.

An indestructible robot would feel __________ as it crossed the event horizon of a black hole.

The densest state of matter found in nature occurs inside a white dwarf star.

During the main-sequence evolution of a massive star,increasingly heavier elements are fused in the core,giving the core support for:

Once carbon begins burning in the core of a high-mass star,the outer layers begin to fall inward,driving up the fusion rates and speeding up the star's evolution primarily because:

Hawking radiation is emitted by a black hole when:

Gravitational lensing allows us to see distant objects that would otherwise be blocked by a star or galaxy.

What are some ways that finding a Cepheid variable star is significant?

The production of large numbers of neutrons in nuclear reactions at the core of a massive star helps rob the core of energy and speeds its eventual collapse.

Which of the following is NOT a common characteristic of a neutron star?

The main difference between Cepheid variable stars and RR Lyrae stars is:

Special relativity says that moving clocks run slower.

Which has a smaller radius,a 2 M ⨀\bigodot⨀ neutron star or a 3 M ⨀\bigodot⨀ neutron star? What supports each of these stars from collapsing to form a black hole?

Black holes emit no light whatsoever.

Our Place in the Universe

Patterns in the Skymotions of Earth

Laws of Motion

Light and Telescopes

The Formation of Stars and Planets

Terrestrial Worlds in the Inner Solar System

Atmospheres of Venus, Earth, and Mars

The Giant Planets

Small Bodies of the Solar System

Measuring the Stars

Our Star: The Sun

Evolution of Low-Mass Stars

The Expansion of Space

The Realm of the Galaxies

Our Galaxy: The Milky Way

Modern Cosmology and the Origin of Structure

Life in the Universe

Filters

Which has a smaller radius,a 2 M_$\bigodot$ neutron star or a 3 M_$\bigodot$ neutron star? What supports each of these stars from collapsing to form a black hole?