Light rays are turned aside by the intense gravitational field surrounding a black hole.A:heightened B:deflected C:rotated D:created

共用题干
B1i'k Holes

1 Black holes can be best described as a sort of vacuum,sucking up everything in space. Scientists
have discovered that black holes come from an explosion of huge stars. Stars that are near death can no longer
burn due to loss of fuel , and because its temperature can no longer control the gravitational（重力的）force,
hydrogen ends up putting pressure onto the star' s surface until it suddenly explodes then collapses.
2 Black holes come from stars that are made of hydrogen,other gases and a few metals. When these
explode it can turn into a stellar-mass ( 恒星质量）black hole , which can only occur if the star is large enough
(should be bigger than the sun) for the explosion to break it into pieces,and the gravity starts to compact
every piece into the tiniest particle. Try to see and compare:if a star that' s ten times the size of the sun ends
up being a black hole that' s no longer than 70 kilometers ,then the Earth would become a black hole that' s
only"fraction of an inch!
3 Objects that get sucked in a black hie will always remain there,never to brsak fren. But remember
that black holes can only gobble up（吞噬）objects within a specific distance to it It' s possible for a large
star near the sun to become a black hole,but the sun will continue to stay in place. Orbits (轨道）do not
change because the newly formed black hole, contains exactly the same amount of mass as when it was a star,
only this time its mass is totally contracted that it can end up as on biggeer tnan a state.
4 So far, astronomers have figured out that black holes exist because of Albert Einstenin's theory of
relativity. In the end,through numerous studies ,they have discovered that black holes truly exist. Since black
holes trap light and do not give off light,it is nearly impossible to detect black goles via a telescope. But
astronomers continue to study galaxies (银河系）,space and the solar system to understand how black holes
misht evolve. It is possible that black holes can exist for millions of years,and later contribute to a bigger
process in galaxies ,which can eventually lead to creation of new entities（实体）.Scientists also credit black
holes as helpful in learning how galaxies began to form.

Paragraph 2_____________
A:What Happens to the Objects Around a Black Hole?
B:Is There Proof That Black Holes Really Exist?
C:How Were Black Holes Named?
D:What Are Different Types of Black Holes?
E:What Are Black Holes Made of?
F:How Are Black Holes Formed?

共用题干
Black Holes

Most scientists agree that black holes exist but are nearly impossible to locate.A black
hole in the universe is not a solid object,like a planet,but it is shaped like a sphere（球体）.
Astronomers（天文学家）think that at the center of a black hole there is a single point in
space with infinite（无限的）density（稠密）.This single point is called a singularity（奇点）.
If the singularity theory is correct,it means that when a massive star collapses,all the
material in it disappears into the singularity.The center of a black hole would not really be a
hole at all,but an infinitely dense point.Anything that crosses the black hole is pulled in by
its great gravity.
Although black holes do exist,they are difficult to observe.These are the reasons.
No light or anything else comes out of black holes.As a result,they are invisible to
a telescope.
In astronomical terms,black holes are truly tiny.For example,a black hole formed
by the collapse of a giant star would have an event horizon（视界）only 18 miles across.
The nearest black holes would be dozens of light years away from Earth.One light
year is about 6 trillion（万亿）miles. Even the most powerlul telescopes could not pick out
an object so small at such a great distance.
In 1994 the Hubble Space Telescope provided evidence that black holes exist.There
are still answers to be found,however,so black holes remain one of the mysteries of the
universe.

The sun is the heaviest star in the universe.
A:Right
B:Wrong
C:Not mentioned

共用题干
Solar Power Without Solar Cells

A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers
could lead to solar power without traditional semiconductor-based solar cells.
The researchers found a way to make an"optical________(51)",said Stephen Rand,a professor in
the departments of Electrical Engineering and Computer Science,Physics and Applied Physics.
Light has electric and magnetic_______(52).Until now,scientists thought the effects of the mag-
netic field were so weak that they could be________(53).What Rand and his colleagues found is that at
the right intensity,when light is traveling through a material that does not_________(54)electricity,the
light field can generate magnetic effects that are 100 million times stronger than previously expected.Under
these circumstances,the magnetic effects develop strength_________(55)to a strong electric effect.
"This could lead to a new kind of solar cell without semiconductors and without absorption to produce
charge separation,"Rand said."In solar cells,the_________(56)goes into a matenal,gets absorbed and
creates heat.Here,we expect to have a very low heat load.Instead of the light being absorbed,energy is
stored in the magnetic moment.Intense magnetization can be induced by intense light and then it is ultimately
capable of providing a capacitive power________(57)."What makes this possible is a previously unde-
tected brand of"optical rectification",says William Fisher,a doctoral student in applied physics.In tradi-
tional optical rectification,light's electric field causes a charge separation,or a pulling_________(58)of
the positive and negative charges in a material.This sets up a voltage,similar to______(59)in a
battery.
Rand and Fisher found that under the right circumstances and in right types of materials,the light's
magnetic field can also create optical rectification.The light must be shone through a________(60)that
does not conduct electricity,such as glass.And it must be focused to an intensity of 10 million watts per
square centimeter. Sunlight isn't this_______(61)on its own,but new materials are being sought that
would work at lower intensities,Fisher said.
"In our most recent paper,we show that incoherent light like sunlight is theoretically almost
_________(62)effective in producing charge separation as laser light is,"Fisher said.
This new_________(63)could make solar power cheaper,the researchers say.They predict that with
improved materials they could achieve 10 percent efficiency in converting solar power to usable energy.That's
equivalent to today's commercial-grade solar cells.
"To manufacture modern solar cells,you have to do. _______(64)semiconductor processing,"
Fisher said."All we would need are lenses to focus the light and a fiber to guide it.Glassworks for
_________ (65).It's already made in bulk,and it doesn't require as much processing.Transparent
ceramics might be even better."

_________(60)
A:material
B:device
C:detector
D:meter

共用题干
Black Holes

1 Black holes can be best described as a sort of vacuum,sucking up everything in space.Scientists
have discovered that black holes come from an explosion of huge stars.Stars that are near death can no longer
burn due to loss of fuel , and because its temperature can no longer control the gravitational（重力的）force,
hydrogen ends up putting pressure onto the star's surface until it suddenly explodes then collapses.
2 Black holes come from stars ihat are made of hydrogen,other gases and a few metals.When these
explode it can turn into a stellar-mass（恒星质量) black hole , which can only occur if the star is large enough
(should be bigger than the sun)for the explosion to break it into pieces,and the gravity starts to compact
every piece into the tiniest particle.Try to see and compare:if a star that's ten times the size of the sun ends
up being a black hole that's no longer than 70 kilometers,then the Earth would become a black hole that'S
only a fraction of an inch!
3 Objects that get sucked in a black hole will always remain there,never to break free.i1it remember
that black holes can only gobble up（吞噬）objects within a specific distance to it.It's possible for a large
star near the sun to become a black hole,but the sun will continue to stay in place.Orbits（轨道）do not
change because the newly formed black hole contains exactly the same amount of mass as when it was a star,
only this time its mass is totally contracted that it can end up as no bigger than a state.
4 Sofar,astronomers have figured out that black holes exist because of Albert Einstcin's theory of
relativity.In the end,through numerous studies,they have discovered that black holes truly exist.Since black
holes trap light and do not give off light,it is nearly impossible to detect black holes via a telescope.But
astronomers continue to study galaxies（银河系）, space and the solar system to understand how black holes
might evolve.It is possible that black holes can exist for millions of years,and later contribute to a bigger
process in galaxies,which can eventually lead to creation of new entities（实体）.Scientists also credit black
holes as helpful in learning how galaxies began to form.

Black holes are formed after_________.
A:the existence of black holes
B:the creation of new entities
C:the same amount of mass
D:an fraction of an inch
E:a fraction of an inch
F:the tiniest particle

共用题干
Solar Power Without Solar Cells

A dramatic and surprising magnetic effect of light discovered by University of Michigan researchers
could lead to solar power without traditional semiconductor-based solar cells.
The researchers found a way to make an"optical________(51)",said Stephen Rand,a professor in
the departments of Electrical Engineering and Computer Science,Physics and Applied Physics.
Light has electric and magnetic_______(52).Until now,scientists thought the effects of the mag-
netic field were so weak that they could be________(53).What Rand and his colleagues found is that at
the right intensity,when light is traveling through a material that does not_________(54)electricity,the
light field can generate magnetic effects that are 100 million times stronger than previously expected.Under
these circumstances,the magnetic effects develop strength_________(55)to a strong electric effect.
"This could lead to a new kind of solar cell without semiconductors and without absorption to produce
charge separation,"Rand said."In solar cells,the_________(56)goes into a matenal,gets absorbed and
creates heat.Here,we expect to have a very low heat load.Instead of the light being absorbed,energy is
stored in the magnetic moment.Intense magnetization can be induced by intense light and then it is ultimately
capable of providing a capacitive power________(57)."What makes this possible is a previously unde-
tected brand of"optical rectification",says William Fisher,a doctoral student in applied physics.In tradi-
tional optical rectification,light's electric field causes a charge separation,or a pulling_________(58)of
the positive and negative charges in a material.This sets up a voltage,similar to______(59)in a
battery.
Rand and Fisher found that under the right circumstances and in right types of materials,the light's
magnetic field can also create optical rectification.The light must be shone through a________(60)that
does not conduct electricity,such as glass.And it must be focused to an intensity of 10 million watts per
square centimeter. Sunlight isn't this_______(61)on its own,but new materials are being sought that
would work at lower intensities,Fisher said.
"In our most recent paper,we show that incoherent light like sunlight is theoretically almost
_________(62)effective in producing charge separation as laser light is,"Fisher said.
This new_________(63)could make solar power cheaper,the researchers say.They predict that with
improved materials they could achieve 10 percent efficiency in converting solar power to usable energy.That's
equivalent to today's commercial-grade solar cells.
"To manufacture modern solar cells,you have to do. _______(64)semiconductor processing,"
Fisher said."All we would need are lenses to focus the light and a fiber to guide it.Glassworks for
_________ (65).It's already made in bulk,and it doesn't require as much processing.Transparent
ceramics might be even better."

_________(61)
A:bright
B:faint
C:visible
D:intense

What will happen several months after the explosion of the star?

A. The star's matter will move further away from by the black hole.
B. The black hole’s matter will heat up.
C. The torn star's matter will swirl into the black hole.
D. The black hole's matter will release ultraviolet light and X-rays.

共用题干
Black Holes

Most scientists agree that black holes exist but are nearly impossible to locate.A black
hole in the universe is not a solid object,like a planet,but it is shaped like a sphere（球体）.
Astronomers（天文学家）think that at the center of a black hole there is a single point in
space with infinite（无限的）density（稠密）.This single point is called a singularity（奇点）.
If the singularity theory is correct,it means that when a massive star collapses,all the
material in it disappears into the singularity.The center of a black hole would not really be a
hole at all,but an infinitely dense point.Anything that crosses the black hole is pulled in by
its great gravity.
Although black holes do exist,they are difficult to observe.These are the reasons.
No light or anything else comes out of black holes.As a result,they are invisible to
a telescope.
In astronomical terms,black holes are truly tiny.For example,a black hole formed
by the collapse of a giant star would have an event horizon（视界）only 18 miles across.
The nearest black holes would be dozens of light years away from Earth.One light
year is about 6 trillion（万亿）miles. Even the most powerlul telescopes could not pick out
an object so small at such a great distance.
In 1994 the Hubble Space Telescope provided evidence that black holes exist.There
are still answers to be found,however,so black holes remain one of the mysteries of the
universe.

The nearest black holes are hundreds of light years away from us.
A:Right
B:Wrong
C:Not mentioned

共用题干
Black Holes

Most scientists agree that black holes exist but are nearly impossible to locate.A black
hole in the universe is not a solid object,like a planet,but it is shaped like a sphere（球体）.
Astronomers（天文学家）think that at the center of a black hole there is a single point in
space with infinite（无限的）density（稠密）.This single point is called a singularity（奇点）.
If the singularity theory is correct,it means that when a massive star collapses,all the
material in it disappears into the singularity.The center of a black hole would not really be a
hole at all,but an infinitely dense point.Anything that crosses the black hole is pulled in by
its great gravity.
Although black holes do exist,they are difficult to observe.These are the reasons.
No light or anything else comes out of black holes.As a result,they are invisible to
a telescope.
In astronomical terms,black holes are truly tiny.For example,a black hole formed
by the collapse of a giant star would have an event horizon（视界）only 18 miles across.
The nearest black holes would be dozens of light years away from Earth.One light
year is about 6 trillion（万亿）miles. Even the most powerlul telescopes could not pick out
an object so small at such a great distance.
In 1994 the Hubble Space Telescope provided evidence that black holes exist.There
are still answers to be found,however,so black holes remain one of the mysteries of the
universe.

The center of a black hole is empty.
A:Right
B:Wrong
C:Not mentioned

共用题干
Black Holes

1 Black holes can be best described as a sort of vacuum,sucking up everything in space.Scientists
have discovered that black holes come from an explosion of huge stars.Stars that are near death can no longer
burn due to loss of fuel , and because its temperature can no longer control the gravitational（重力的）force,
hydrogen ends up putting pressure onto the star's surface until it suddenly explodes then collapses.
2 Black holes come from stars ihat are made of hydrogen,other gases and a few metals.When these
explode it can turn into a stellar-mass（恒星质量) black hole , which can only occur if the star is large enough
(should be bigger than the sun)for the explosion to break it into pieces,and the gravity starts to compact
every piece into the tiniest particle.Try to see and compare:if a star that's ten times the size of the sun ends
up being a black hole that's no longer than 70 kilometers,then the Earth would become a black hole that'S
only a fraction of an inch!
3 Objects that get sucked in a black hole will always remain there,never to break free.i1it remember
that black holes can only gobble up（吞噬）objects within a specific distance to it.It's possible for a large
star near the sun to become a black hole,but the sun will continue to stay in place.Orbits（轨道）do not
change because the newly formed black hole contains exactly the same amount of mass as when it was a star,
only this time its mass is totally contracted that it can end up as no bigger than a state.
4 Sofar,astronomers have figured out that black holes exist because of Albert Einstcin's theory of
relativity.In the end,through numerous studies,they have discovered that black holes truly exist.Since black
holes trap light and do not give off light,it is nearly impossible to detect black holes via a telescope.But
astronomers continue to study galaxies（银河系）, space and the solar system to understand how black holes
might evolve.It is possible that black holes can exist for millions of years,and later contribute to a bigger
process in galaxies,which can eventually lead to creation of new entities（实体）.Scientists also credit black
holes as helpful in learning how galaxies began to form.

When a large star explodes,the gravity compacts every piece into______.
A:the existence of black holes
B:the creation of new entities
C:the same amount of mass
D:an fraction of an inch
E:a fraction of an inch
F:the tiniest particle

共用题干
Black Holes

1 Black holes can be best described as a sort of vacuum,sucking up everything in space.Scientists
have discovered that black holes come from an explosion of huge stars.Stars that are near death can no longer
burn due to loss of fuel , and because its temperature can no longer control the gravitational（重力的）force,
hydrogen ends up putting pressure onto the star's surface until it suddenly explodes then collapses.
2 Black holes come from stars ihat are made of hydrogen,other gases and a few metals.When these
explode it can turn into a stellar-mass（恒星质量) black hole , which can only occur if the star is large enough
(should be bigger than the sun)for the explosion to break it into pieces,and the gravity starts to compact
every piece into the tiniest particle.Try to see and compare:if a star that's ten times the size of the sun ends
up being a black hole that's no longer than 70 kilometers,then the Earth would become a black hole that'S
only a fraction of an inch!
3 Objects that get sucked in a black hole will always remain there,never to break free.i1it remember
that black holes can only gobble up（吞噬）objects within a specific distance to it.It's possible for a large
star near the sun to become a black hole,but the sun will continue to stay in place.Orbits（轨道）do not
change because the newly formed black hole contains exactly the same amount of mass as when it was a star,
only this time its mass is totally contracted that it can end up as no bigger than a state.
4 Sofar,astronomers have figured out that black holes exist because of Albert Einstcin's theory of
relativity.In the end,through numerous studies,they have discovered that black holes truly exist.Since black
holes trap light and do not give off light,it is nearly impossible to detect black holes via a telescope.But
astronomers continue to study galaxies（银河系）, space and the solar system to understand how black holes
might evolve.It is possible that black holes can exist for millions of years,and later contribute to a bigger
process in galaxies,which can eventually lead to creation of new entities（实体）.Scientists also credit black
holes as helpful in learning how galaxies began to form.

Paragraph 1________
A:What Happens to the Objects Around a Black Hole?
B:Is There Proof That Black Holes Really Exist?
C:How Were Black Holes Named?
D:What Are Different Types of Black Holes?
E:What Are Black Holes Made of?
F: How Are Black Holes Formed?

Black Holes Trigger Stars to Self-Destruct
　　Scientists have long understood that supermassive black holes weighing millions or billions of suns can tear apart stars that come too close. The black hotels gravity pulls harder on the nearest part of the star, an imbalance that pulls the star apart over a period of minutes or hours, once it gets close enough.
　　Scientists say this Uneven pulling is not the only hazard facing the star. The strain of these unbalanced forces can also trigger a nuclear explosion powerful enough to destroy the star from within. Matthieu Brassart and Jean-Pierre Luminet of the Observatoire de Paris in Meudon, France, carried out computer simulations of the final moments of such an unfortunate star's life,as it veered towards a supermassive black hole.
　　When the star gets close enough, the uneven forces flatten it into a pancake shape. Some previous studies had suggested this flattening would increase the density and temperature inside the star enough to trigger intense nuclear reactions that would tear it apart. But other studies had suggested that the picture would be complicated by shock waves generated during the flattening process and that no nuclear explosion should occur.
　　The new simulations investigated the effects of shock waves in detail,and found that even when their effects are included,the conditions favor a nuclear explosion. "There will be an explosion of the star-it will be completely destroyed," Brassart says. Although the explosion obliterates the star, it saves some of the star's matter from being devoured by the black hole. The explosion is powerful enough to hurl much of the star's matter out of the black hole's reach, he says.
　　The devouring of stars by black holes may already have been observed, although at a much later stage. It is thought that several months after the event that rips the star apart,its matter starts swirling into the hole itself. It heats up as it does so, releasing ultraviolet light and X-rays.
　　If stars disrupted near black holes really do explode, then they could in principle allow these events to be detected at a much earlier stage, says Jules Hatpern of Columbia University in New York, US. "It may make it possible to see the disruption of that star immediately if it gets hot enough," he says.
　　Brassart agrees. "Perhaps it can be observed in the X-rays and gamma rays, but it's something that needs to be more studied," he says. Supernova researcher Chris Fryer of the Los Alamos National Laboratory in Los Alamos, New Mexico, US, says the deaths of these stars are difficult to simulate, and he is not sure whether the researchers have proven their case that they explode in the process.
文章(36~40)

Something destructive could happen to a star that gets too close to a black hole. Which of the following destructive statements is NOT mentioned in the passage?

A. The black hole could tear apart the star.
B. The black hole could trigger a nuclear explosion in the star.
C. The black hole could dwindle its size considerably.
D. The black hole could devour the star.