Question 1

The escape speed for a black hole's event horizon is the speed of light.

Accepted Answer

A) True 
 B)False  True

Question 2

A method for identifying a black hole is to

Accepted Answer

A)  look for voids in the star fields. 
B)  look for their effects on nearby companions. 
C)  locate a visible star that disappears when the black hole passes in front of it. 
D)  search for radio waves from the accretion disk. 
E)  search for their pulsar signal. 
A)  look for voids in the star fields. 
B)  look for their effects on nearby companions. 
C)  locate a visible star that disappears when the black hole passes in front of it. 
D)  search for radio waves from the accretion disk. 
E)  search for their pulsar signal. B

Question 3

As a spaceship approaches the event horizon of a black hole, its radio transmissions would

Accepted Answer

A)  be sucked into the black hole. 
B)  shifted to infrared or even visible light. 
C)  shifted to longer wavelength. 
D)  increase in amplitude. 
E)  be unchanged. 
A)  be sucked into the black hole. 
B)  shifted to infrared or even visible light. 
C)  shifted to longer wavelength. 
D)  increase in amplitude. 
E)  be unchanged. C

Question 4

If the Sun were to magically and instantaneously be replaced by a 1 solar mass black hole, what would happen to the Earth's orbit?

Accepted Answer

A)  It would be unchanged. 
B)  It would be much smaller, but its shape would be unchanged. 
C)  It would be at the same distance from the Sun, but would be much more eccentric. 
D)  It would be much larger, but its shape would be unchanged. 
E)  The Earth would be pulled into the black hole and destroyed. 
A)  It would be unchanged. 
B)  It would be much smaller, but its shape would be unchanged. 
C)  It would be at the same distance from the Sun, but would be much more eccentric. 
D)  It would be much larger, but its shape would be unchanged. 
E)  The Earth would be pulled into the black hole and destroyed.

Question 5

If the Sun were replaced by a one solar mass black hole

Accepted Answer

A)  all terrestrial planets would fall in immediately. 
B)  we would still orbit it in a period of one year. 
C)  we would immediately escape into deep space, driven out by its radiation. 
D)  our clocks would all stop. 
E)  life here would be unchanged. 
A)  all terrestrial planets would fall in immediately. 
B)  we would still orbit it in a period of one year. 
C)  we would immediately escape into deep space, driven out by its radiation. 
D)  our clocks would all stop. 
E)  life here would be unchanged.

Question 6

The singularity of a black hole is

Accepted Answer

A)  where general relativity predicts the density to be zero. 
B)  where the current understanding of gravity is incomplete. 
C)  the point at which nothing, not even light, can escape. 
D)  the region between the Schwarzschild Radius and the event horizon. 
A)  where general relativity predicts the density to be zero. 
B)  where the current understanding of gravity is incomplete. 
C)  the point at which nothing, not even light, can escape. 
D)  the region between the Schwarzschild Radius and the event horizon.

Question 7

Material that falls into a black hole can be seen by the electromagnetic radiation it emits before it reaches the event horizon.

Accepted Answer

A) True 
 B)False

Question 8

What explanation does general relativity provide for gravity?

Accepted Answer

A)  Gravity is the result of curved spacetime. 
B)  Gravity is directly proportional to the mass of the attracting body. 
C)  Gravity is inversely proportion to the radius of the body. 
D)  Gravity is the opposite of the electromagnetic force. 
E)  Gravity can affect only massive particles, not massless photons. 
A)  Gravity is the result of curved spacetime. 
B)  Gravity is directly proportional to the mass of the attracting body. 
C)  Gravity is inversely proportion to the radius of the body. 
D)  Gravity is the opposite of the electromagnetic force. 
E)  Gravity can affect only massive particles, not massless photons.

Question 9

If a neutron star attains a mass over ________ solar masses it becomes a black hole.

Accepted Answer

The answer of If a neutron star attains a mass...

Question 10

The observed slowing of a clock in the vicinity of a black hole is a prediction of

Accepted Answer

A)  the Roche Limit. 
B)  Special relativity. 
C)  General relativity. 
D)  Stellar nucleosynthesis. 
E)  the Cosmological Principle. 
A)  the Roche Limit. 
B)  Special relativity. 
C)  General relativity. 
D)  Stellar nucleosynthesis. 
E)  the Cosmological Principle.

Question 11

The densely packed neutrons of a neutron star cannot balance the inward pull of gravity if the total mass is

Accepted Answer

A)  less than 1.0 solar masses. 
B)  greater than Schwartzschild's limit of 3 solar masses. 
C)  Chandrasekhar's limit of 1.4 solar masses. 
D)  between 1.4 and 2.0 solar masses. 
E)  greater than 25 solar masses. 
A)  less than 1.0 solar masses. 
B)  greater than Schwartzschild's limit of 3 solar masses. 
C)  Chandrasekhar's limit of 1.4 solar masses. 
D)  between 1.4 and 2.0 solar masses. 
E)  greater than 25 solar masses.

Question 12

In 1921, the Nobel Prize in physics was awarded to ________ for his work on the particle nature of light.

Accepted Answer

The answer of In 1921, the Nobel Prize in physics...

Question 13

What is Cygnus X-1?

Accepted Answer

A)  The brightest star in the constellation Cygnus 
B)  The leading candidate for an observable black hole binary system 
C)  The strongest X-ray eclipsing binary system in the sky 
D)  A millisecond pulsar with three Earth-like planets around it 
E)  The first gamma-ray burster to be spotted in other wavelengths as well 
A)  The brightest star in the constellation Cygnus 
B)  The leading candidate for an observable black hole binary system 
C)  The strongest X-ray eclipsing binary system in the sky 
D)  A millisecond pulsar with three Earth-like planets around it 
E)  The first gamma-ray burster to be spotted in other wavelengths as well

Question 14

What is some of the evidence that Cygnus X-1 is a black hole?

Accepted Answer

The mass of the invisible object, based

Question 15

Which of the following are attracted by gravity?

Accepted Answer

A)  Antimatter 
B)  Any object with mass 
C)  Dlectromagnetic radiation 
D)  Neutrinos 
E)  All of the above 
A)  Antimatter 
B)  Any object with mass 
C)  Dlectromagnetic radiation 
D)  Neutrinos 
E)  All of the above

Question 16

An accelerating frame of reference cannot be distinguished from a gravitational field.

Accepted Answer

A) True 
 B)False

Question 17

On the surface of a sphere the shortest distance between two points is

Accepted Answer

A)  an arc on a great circle. 
B)  a straight line. 
C)  a circle. 
D)  a triangle. 
E)  a curvy line. 
A)  an arc on a great circle. 
B)  a straight line. 
C)  a circle. 
D)  a triangle. 
E)  a curvy line.

Question 18

The current theories of gravity are ________ because they do not incorporate a proper description of matter on the smallest scale.

Accepted Answer

The answer of The current theories of gravity are ________...

Question 19

If you were to fall into a black hole, the ________ would kill you by tearing you apart.

Accepted Answer

The answer of If you were to fall into a...

Question 20

According to general relativity, objects moved on curved paths due to the force of gravity.

Accepted Answer

A) True 
 B)False

The escape speed for a black hole's event horizon is the speed of light.

A method for identifying a black hole is to

As a spaceship approaches the event horizon of a black hole, its radio transmissions would

If the Sun were to magically and instantaneously be replaced by a 1 solar mass black hole, what would happen to the Earth's orbit?

If the Sun were replaced by a one solar mass black hole

The singularity of a black hole is

Material that falls into a black hole can be seen by the electromagnetic radiation it emits before it reaches the event horizon.

What explanation does general relativity provide for gravity?

If a neutron star attains a mass over ________ solar masses it becomes a black hole.

The observed slowing of a clock in the vicinity of a black hole is a prediction of

The densely packed neutrons of a neutron star cannot balance the inward pull of gravity if the total mass is

In 1921, the Nobel Prize in physics was awarded to ________ for his work on the particle nature of light.

What is Cygnus X-1?

What is some of the evidence that Cygnus X-1 is a black hole?

Which of the following are attracted by gravity?

An accelerating frame of reference cannot be distinguished from a gravitational field.

On the surface of a sphere the shortest distance between two points is

The current theories of gravity are ________ because they do not incorporate a proper description of matter on the smallest scale.

If you were to fall into a black hole, the ________ would kill you by tearing you apart.

According to general relativity, objects moved on curved paths due to the force of gravity.

The Night Sky

Light and Telescopes

The Solar System

Earth and Its Moon

The Eight Planets

Small Bodies in the Solar System

Formation of Planetary Systems

The Sun

Measuring the Stars

Star Formation and Evolution

Stellar Explosions

The Milky Way Galaxy

Galaxies

Cosmology and the Universe

Filters

Exam 12: Black Holes

The escape speed for a black hole's event horizon is the speed of light.

A method for identifying a black hole is to

As a spaceship approaches the event horizon of a black hole, its radio transmissions would

If the Sun were to magically and instantaneously be replaced by a 1 solar mass black hole, what would happen to the Earth's orbit?

If the Sun were replaced by a one solar mass black hole

The singularity of a black hole is

Material that falls into a black hole can be seen by the electromagnetic radiation it emits before it reaches the event horizon.

What explanation does general relativity provide for gravity?

If a neutron star attains a mass over ________ solar masses it becomes a black hole.

The observed slowing of a clock in the vicinity of a black hole is a prediction of

The densely packed neutrons of a neutron star cannot balance the inward pull of gravity if the total mass is

In 1921, the Nobel Prize in physics was awarded to ________ for his work on the particle nature of light.

What is Cygnus X-1?

What is some of the evidence that Cygnus X-1 is a black hole?

Which of the following are attracted by gravity?

An accelerating frame of reference cannot be distinguished from a gravitational field.

On the surface of a sphere the shortest distance between two points is

The current theories of gravity are ________ because they do not incorporate a proper description of matter on the smallest scale.

If you were to fall into a black hole, the ________ would kill you by tearing you apart.

According to general relativity, objects moved on curved paths due to the force of gravity.

The Night Sky

Light and Telescopes

The Solar System

Earth and Its Moon

The Eight Planets

Small Bodies in the Solar System

Formation of Planetary Systems

The Sun

Measuring the Stars

Star Formation and Evolution

Stellar Explosions

The Milky Way Galaxy

Galaxies

Cosmology and the Universe

Filters