GIÚP EM VỚI Ạ,EM CẦN GẤPPEarth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of...

TM

The Moon

31 tháng 12 2021

GIÚP EM VỚI Ạ,EM CẦN GẤPPEarth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent.Solar eclipses are easily the more spectacular of the two. For a solar eclipse to occur, the moon’s orbit must take...

Đọc tiếp

GIÚP EM VỚI Ạ,EM CẦN GẤPP

Earth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent.

Solar eclipses are easily the more spectacular of the two. For a solar eclipse to occur, the moon’s orbit must take it between Earth and the sun. while the sun is much larger than the moon, the relative nearness of the moon to Earth makes it appear to be the same size as the sun when viewed from the ground. Thus, when the sun, Earth, and moon are perfectly aligned, the moon appears to cover the entire sun. this is a solar eclipse. A solar eclipse may be either total or partial. When a total eclipse happens, the sun is completely obscured by the moon. The sky darkens, and it appears to be night time. However, most solar eclipse are partial ones. When they take place, the sun is only partly covered by the moon.

When a solar eclipse happens, it is observable from a fairly small area on the planet. Thus, when there is a solar eclipse in North America, it is highly unlikely that it will be visible in Africa or Australia. A solar eclipse only lasts for a few minutes since all three heavenly bodies are in continual motion. People must also take care when viewing a solar eclipse since looking directly at it can cause damage – including blindness – to their eyes.

Lunar eclipses happen when Earth moves directly between the sun and the moon. When this occurs, the planet blocks sunlight from reflecting off the moon. Lunar eclipses take place at night. During one, the moon appears very orange and is practically red in color. There are two different types of lunar eclipses. Taken together, the result is that lunar eclipses happen more frequently than solar eclipses. In addition, lunar eclipses may last for hours and can be seen from a wider area on the planet. There is no harm in directly observing a lunar eclipse either, so looking at one will not damage a person’s eyes.

28. What was the passage mainly about?
A. How eclipses have affected history

B. Two types of eclipses
C. The problems eclipses cause

D. Solar eclipses
29. What is the word ‘spectacular’ in line 5 closest in meaning to?
A. distinct

B. impressive
C. lost lasting

D. common
30. Why is the moon able to cover the sun during a solar eclipse?
A. Because of its large size

B. Because of its brightness

C. Because of its closeness to Earth .

D. Because of its rotation
31. Which of the following is NOT mentioned about solar eclipses?
A. How they can harm people

B. How long they may last

C. How much of the sun cannot be seen during them

D. How often they happen
32. What can be inferred from the passage about lunar eclipses?
A. It is possible to see them from every-where in the world

B. They are less dangerous to people than solar eclipses

C. Superstitious people believe they bring bad luck

D. During a full moon, they can be extremely bright.

#Tiếng anh lớp 9

0

C

changchan

17 tháng 11 2021

Earth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent. Solar eclipses are easily the more spectacular of the two. For a solar eclipse to occur, the moon's orbit must take it between Earth and...

Đọc tiếp

Earth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent.

Solar eclipses are easily the more spectacular of the two. For a solar eclipse to occur, the moon's orbit must take it between Earth and the sun. While the sun is much larger than the moon, the relative nearness of the moon to Earth makes it appear to be the same size as the sun when viewed from the ground. Thus, when the sun, Earth, and moon are perfectly aligned, the moon appears to cover the entire sun. This is a solar eclipse. A solar eclipse may be either total or partial. When a total eclipse happens, the sun is completely obscured by the moon. The sky darkens, and it appears to be night time. However, most solar eclipses are partial ones. When they take place, the sun is only partly covered by the moon.

When a solar eclipse happens, it is observable from a fairly small area on the planet. Thus, when there is a solar eclipse in North America, it is highly unlikely that it will be visible in Africa or Australia. A solar eclipse only lasts for a few minutes since all three heavenly bodies are in continual motion. People must also take care when viewing a solar eclipse since looking directly at it can cause damage - including blindness - to their eyes.

Lunar eclipses happen when Earth moves directly between the sun and the moon. When this occurs, the planet blocks sunlight from reflecting off the moon. Lunar eclipses take place at night. During one, the moon appears very orange and is practically red in color. There are two different types of lunar eclipses. Taken together, the result is that lunar eclipses happen more frequently than solar eclipses. In addition, lunar eclipses may last for hours and can be seen from a wider area on the planet. There is no harm in directly observing a lunar eclipse either, so looking at one will not damage a person's eyes.

28. What is the passage mainly about?

A. How eclipses have affected history B. Two types of eclipses

C. The problems eclipses cause D. Solar eclipses

29. What is the word ‘spectacular’ in line 5 closest in meaning to?

A. distinct B. impressive C. lost lasting D. common

30. Why is the moon able to cover the sun during a solar eclipse?

A. Because of its large size B. Because of its brightness

C. Because of its closeness to Earth D. Because of its rotation

31. Which of the following is NOT mentioned about solar eclipses?

A. How they can harm people

B. How long they may last

C. How much of the sun cannot be seen during them

D. How often they happen

32. What can be inferred from the passage about lunar eclipses?

A. It is possible to see them from every-where in the world.

B. They are less dangerous to people than solar eclipses.

C. Superstitious people believe they bring bad luck.

D. During a full moon, they can be extremely bright.

#Tiếng anh lớp 9

1

PT

Phạm Thị Hiền

17 tháng 11 2021

Ko biết làm ok bạn

Đúng(0)

C

changchan

19 tháng 11 2021

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. Earth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent. ...

Đọc tiếp

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.

Earth orbits the sun while the moon orbits Earth. Occasionally, all three of them become aligned with one another. When this happens, an eclipse occurs. There are two types of eclipses: solar and lunar. Both are rare events simply because, due to the movement of all three celestial bodies, the times when they line up with one another are infrequent.

Solar eclipses are easily the more spectacular of the two. For a solar eclipse to occur, the moon's orbit must take it between Earth and the sun. While the sun is much larger than the moon, the relative nearness of the moon to Earth makes it appear to be the same size as the sun when viewed from the ground. Thus, when the sun, Earth, and moon are perfectly aligned, the moon appears to cover the entire sun. This is a solar eclipse. A solar eclipse may be either total or partial. When a total eclipse happens, the sun is completely obscured by the moon. The sky darkens, and it appears to be night time. However, most solar eclipses are partial ones. When they take place, the sun is only partly covered by the moon.

When a solar eclipse happens, it is observable from a fairly small area on the planet. Thus, when there is a solar eclipse in North America, it is highly unlikely that it will be visible in Africa or Australia. A solar eclipse only lasts for a few minutes since all three heavenly bodies are in continual motion. People must also take care when viewing a solar eclipse since looking directly at it can cause damage - including blindness - to their eyes.

Lunar eclipses happen when Earth moves directly between the sun and the moon. When this occurs, the planet blocks sunlight from reflecting off the moon. Lunar eclipses take place at night. During one, the moon appears very orange and is practically red in color. There are two different types of lunar eclipses. Taken together, the result is that lunar eclipses happen more frequently than solar eclipses. In addition, lunar eclipses may last for hours and can be seen from a wider area on the planet. There is no harm in directly observing a lunar eclipse either, so looking at one will not damage a person's eyes.

28. What is the passage mainly about?

A. How eclipses have affected history B. Two types of eclipses

C. The problems eclipses cause D. Solar eclipses

29. What is the word ‘spectacular’ in line 5 closest in meaning to?

A. distinct B. impressive C. lost lasting D. common

30. Why is the moon able to cover the sun during a solar eclipse?

A. Because of its large size B. Because of its brightness

C. Because of its closeness to Earth D. Because of its rotation

31. Which of the following is NOT mentioned about solar eclipses?

A. How they can harm people

B. How long they may last

C. How much of the sun cannot be seen during them

D. How often they happen

32. What can be inferred from the passage about lunar eclipses?

A. It is possible to see them from everywhere in the world.

B. They are less dangerous to people than solar eclipses.

C. Superstitious people believe they bring bad luck.

D. During a full moon, they can be extremely bright.

#Tiếng anh lớp 9

0

ND

Nguyễn Đỗ ánh

11 tháng 12 2017

Read the dialogue and then decide whether the statements that follow are true or false. Write True or False in your answersheet: A planet is a body in space that revolves around a star. There are nine planets in our solar system, and these nine planets travel around the sun. The names of the planets are Mercury, Venus, Earth, Jupiter, Saturn, Uranus, Neptune, and Pluto. Planets travel in orbits around their stars . All of the planets of the solar system revolve in elliptical orbits. In...

Đọc tiếp

#Tiếng anh lớp 9

1

KV

Kook V (I love BTS)

14 tháng 12 2017

__TRUE__ 1/ A planet revolves around the Earth.

__TRUE__2/ Venus, Mars and Neptune are planets and stars.

__TRUE__ 3/ The Greek were the first to recognize some of the planets.

__TRUE__ 4/ The planets in our solar system travel around the sun and in elliptical orbits .

Sao đúng hết vậy ta ( có thể câu 2 là FALSE nhé bạn ) tớ học Anh Văn cũng không tốt lắm đâu . Đúng thì like cho tớ vui vưới nhé !

Đúng(1)

LT

Lục Thiên Hy

10 tháng 2 2020

Passage 1: FENG SHUI Feng Shui is the ancient Chinese art of bringing balance to one’s immediate (1) ________ (ROUND). It aims to harness energy flow within the home to make it a nice, healthy place in which to live. Although in the West it has only recently gained (2) ________ (ACCEPT) in China, it is deemed (3) __________ (DISPENSE) to have recourse to a Feng Shui (4) ____________ (PRACTICE) before moving house or (5) ____________ (ESTABLISH) a business. On a mundane level, it is the art of...

Đọc tiếp

Passage 1: FENG SHUI

Feng Shui is the ancient Chinese art of bringing balance to one’s immediate (1) ________ (ROUND). It aims to harness energy flow within the home to make it a nice, healthy place in which to live. Although in the West it has only recently gained (2) ________ (ACCEPT) in China, it is deemed (3) __________ (DISPENSE) to have recourse to a Feng Shui (4) ____________ (PRACTICE) before moving house or (5) ____________ (ESTABLISH) a business. On a mundane level, it is the art of furniture placement, but it being (6) _____________ (HAUL) thoroughly, (7) ____________ (MEAN) philosophical and religious roots are found (8) ____________ (PIN) this (9) ____________ (VENERATE) art form. The Taoist philosophy out of which it grew sees the world as made up of potent but invisible energy called ‘chi’. Feng Shui aspires to divert this hidden flow to create a (10) _____________ (HARMONY) environment. Although this is a(n) (11) ____________ (FAMILIAR/ CUSTOM) concept to the Western world, the (12) ___________ (SURGE / SWING / TURN) of Feng Shui continues (13) _____________ (ABATE). Feng Shui offers some (14) ______________ (ESSENTIAL) rules with which to augment the potential of one’s environment. (15) ____________ (MOVE) of (16) ___________ (ARRAY) is said to promote feelings of (17) ____________ (LUCID) and calmness. The utilization of plants (18) ____________ (ACT) the detrimental effect of machinery, computers and so on. Finally, because chi energy enters through the front door, it is (19) _____________ (VISION / SIGHT) to keep one’s door in perfect condition to take away any (20) __________ (IMPEDE) to the passage of entering chi energy.

Passage 2: Read the text below and think of the word which best fits each gap. Use only ONE word in each gap. Write your answers in corresponding numbered boxes. There is an example at the beginning (0).

Example: 0. when

THE BLOOD MOON

A lunar eclipse occurs (0) _____________the Earth’s shadow falls directly onto the moon. (1) _____________ happens as a result is that the moon stops being a silvery white colour and turns coppery red instead; the sort of colour usually only seen in the sky at dawn or sunset. An astronaut on the moon, looking towards Earth (2) ____________ a lunar eclipse, would see a black disc, surrounded (3) _____________a bright red ring. It’s the light from this red ring which is reflected back to the dark Earth from the moon’s surface. In ancient times, long (4) ______________ any of this was understood, the lunar eclipse was known (5) _____________a blood moon and was thought to be an omen of disaster.

Total eclipses can only occur when there is a full moon, and then only if it is lined (6) ____________ with the Earth in a particular way. (7) ______________easily obscured by cloud cover, blood moons are fairly common, and it is relatively easy to calculate where and when you might be (8) _____________ to see one.

For example, in 1504 Christopher Columbus was stranded in Jamaica and (9) ____________ dire need of provisions, but the local inhabitants were reluctant to help. Columbus knew that a lunar eclipse would occur on 29 February, however. So, the day before, he warned local leaders that the moon would disappear (10) ____________ they helped him. They remained skeptical. But when the moon slowly started to change colour, they became so frightened that they started to bring food.

Mọi người giúp em với ạ, em cảm ơn

#Tiếng anh lớp 9

0

LQ

Lê Quỳnh Anh

16 tháng 2 2017

Read the following passage and then choose the best answer A, B, C or D.Comets are bodies that move around in space. They are something likes stars or small planets that move around the sun. Comets are surrounded by gases and the sun makes those gases look very bright. Dust can get caught in the gas around the comet and make the comet look like it has a tails.Halley's Comet is the most famous comet, but we can't see it very often. In fact, it can only be seen from the Earth when it moves close...

Đọc tiếp

Read the following passage and then choose the best answer A, B, C or D.

Comets are bodies that move around in space. They are something likes stars or small planets that move around the sun. Comets are surrounded by gases and the sun makes those gases look very bright. Dust can get caught in the gas around the comet and make the comet look like it has a tails.

Halley's Comet is the most famous comet, but we can't see it very often. In fact, it can only be seen from the Earth when it moves close the sun. This means that this beautiful comet only comes into our sky every 77 years or so. The last time Halley's Comet was invisible from the Earth was in 1991. Did you see it?

Halley's Comet was named after the English astronomer Edmond Halley. An astronomer studies the star and planets in the solar system. Edmond Halley was born in London, England, in 1656. He studies astronomy at Oxford University. In 1676, he left the university to study the astronomy of the Southern Hemisphere. He wrote a brook about the arrangement of the stars in the sky and the movement of the planets. He made the first accurate map of the stars we see in the sky. He also observed the moon and studied how the Moon affects the ocean tides. He helped find a way to measure distances in space. This measurement was used by other scientists to learn about the size of our solar system and the distances of many star and planets from the Earth.

Halley especially liked to study comets. He read about comets and observed them in the sky. He learned about the way they moved around the Sun — each comet follows a different path around the Sun and travels at its own speed. The path and speed of a body as it moves in space is called its orbit. Halley calculated the orbits of comets that he read about or saw himself. He found the orbits for twenty-four comets.

Halley also noticed that the paths of a comet seen in 1531 and of a comet seen in 1607 were identical to the path of a comet he had observed in 1682. He concluded that these three comets were, in fact, the same comet. Halley predicted that the comet would come again in 1758, and it did! This comet was named “Halley’s Comet” and can be seen from Earth. The first reports of this comet in history were made in 240 B.C. by Chinese astronomers, so we know that it has been orbiting the Sun to more than 2,000 years. Halley’s Comet is not the only comet in our sky, but it is the only one that appears regularly and can be predicted. It is also one of the brightest comets, and people can see it without a telescope.

Like comets, the Earth also travels around the Sun. Sometimes the orbit of t Earth passes through the path of Hailey’s Comet. Like comets, the Earth also travels around the Sun. Sometimes the orbit of the Earth passes through the path of Hailey’s Comet. When this When this happens, dust left behind from the comet falls to Earth. The dust burns and makes brilliant lights like falling stars in the sky. You can see this happen every year in May and October. Astronomers predict that Hailey’s Comet will enter our sky again in 2061. Who do you think will see it?

Edmond Hailey calculated the orbits for _______

A. 1607

B. 1682

C. 77 comets

D. 24 comets

#Mẫu giáo

1

DH

Dương Hoàn Anh

16 tháng 2 2017

Đáp án D

Đáp án nằm ở hai câu cuối đoạn số 4: Halley calculated the orbits of comets that he read about or saw
himself. He found the orbits for twenty-four comets

Đúng(0)

LQ

Lê Quỳnh Anh

13 tháng 7 2017

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

Đọc tiếp

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

The phrase one another in paragraph 3 refers to

A. Particles

B. Electrical charges

C. Electrons

D. Atoms

#Mẫu giáo

1

DH

Dương Hoàn Anh

13 tháng 7 2017

Đáp án là B

Cụm từ “ one another” ở đoạn 3 ám chỉ đến

A. Các phân tử

B. Các điện cực

C. Các electron

D. Các nguyên tử

Dẫn chứng: Opposite electrical charges attract one another [ Những điện cực ngược nhau sẽ hút lẫn nhau]

Đúng(0)

LQ

Lê Quỳnh Anh

22 tháng 9 2018

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade...

Đọc tiếp

Read the following passage, and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles. There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units do not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun .In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than of the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas .This explanation, however, is of little use to most average people.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers; their atomic number , which is equal to the number of protons they have, and their atomic weight , which is equal to total number of their neutrons and protons. In most lighter atoms , the number of neutrons and protons is equal , and the element is stable. In heavier atoms, however, there are more neutrons than protons , and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbit. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electron than the previous shell. Electrons naturally seek to occupy the lowest shell possible .So if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light .This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When it happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms.

According to the passage, all of the following are true of electrons EXCEPT

A. Their energy levels are fixed and unchanging

B. They are kept in orbit by electromagnetic attraction

C. They are elementary particles and cannot be broken down

D. They are considerably smaller than neutrons or protons

#Mẫu giáo

1

DH

Dương Hoàn Anh

22 tháng 9 2018

Đáp án là A

Theo bài đọc, tất cả những ý nào sau đây đúng về electron NGOẠI TRỪ

A. Mức năng lượng của chúng là cố định và không đổi.

B. Chúng được giữ trong quỹ đạo bởi những lực hấp dẫn mang điện cực.

C. Chúng là những phân tử cơ bản và không thể bị phá vỡ

D. Chúng nhỏ hơn rất nhiều so với các notron và proton.

Dẫn chứng:

They are bound to their atoms through electromagnetic attraction. =>loại B

Electrons are different from neutrons in that they cannot be broken down into smaller particles. => loại C và D

Đúng(0)

LQ

Lê Quỳnh Anh

8 tháng 2 2019

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. There is a common expression in the English language referring to a blue moon. When people say that something happens “only once in a blue moon,” they mean that it happens only very rarely, once in a great while. This expression has been around for at least a century and a half; there are references to this expression that date from the second half of...

Đọc tiếp

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

There is a common expression in the English language referring to a blue moon. When people say that something happens “only once in a blue moon,” they mean that it happens only very rarely, once in a great while. This expression has been around for at least a century and a half; there are references to this expression that date from the second half of the nineteenth century. (5) The expression “a blue moon” has come to refer to the second full moon occurring in any given calendar month. A second full moon is not called a blue moon because it is particularly blue or is any different in hue from the first full moon of the month. Instead, it is called a blue moon because it is so rare. The moon needs a little more than 29 days to complete the cycle from full moon to full moon. Because every month except February has more than 29 days, every month will have at least one full moon (except February, which will have a full moon unless there is a full moon at the very end of January and another full moon at the very beginning of March). It is on the occasion when a given calendar month has a second full moon that a blue moon occurs. This does not happen very often, only three or four times in a decade. The blue moons of today are called blue moons because of their rarity and not because of their color; however, the expression “blue moon” may have come into existence in reference to unusual circumstances in which the moon actually appeared blue. Certain natural phenomena of gigantic proportions can actually change the appearance of the moon from Earth. The eruption of the Krakatao volcano in 1883 left dust particles in the atmosphere, which clouded the sun and gave the moon a bluish tint. This particular occurrence of the blue moon may have given rise to the expression that we use today. Another example occurred more than a century later. When Mount Pinatubo erupted in the Philippines in 1991, the moon again took on a blue tint.

How many blue moons would there most likely be in a century?

A. 4

B. 35

C. 70

D. 100

#Mẫu giáo

1

DH

Dương Hoàn Anh

8 tháng 2 2019

Answer B

Kỹ năng: Đọc

Giải thích:

Trong một thế kỷ, có thể có 35 trăng xanh. Thông tin ở câu cuối đoạn 2: “ this does not happen very often, only three or four times in a decade.” (Điều này không xảy ra thường xuyên, chỉ 3 hoặc 4 lần trong một thập kỷ.) Do đó, trong mọt thế kỷ, sẽ có khoảng 30 – 40 trăng xanh. Đáp án B là hoàn toàn phù hợp.

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LQ

Lê Quỳnh Anh

27 tháng 1 2018

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by...

Đọc tiếp

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.

Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.

Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When this happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms

According to the passage, all of the following are true of electrons EXCEPT __________.

A. they are elementary particles and cannot be broken down

B. they are considerably smaller than neutrons or protons

C. their energy levels are fixed and unchanging

D. they are kept in orbit by electromagnetic attraction

#Mẫu giáo

1

DH

Dương Hoàn Anh

27 tháng 1 2018

Chọn C

Kiến thức: Đọc hiểu

Giải thích:

Theo đoạn văn, tất cả những điều sau đây đều đúng với các electron NGOẠI TRỪ __________.

A. chúng là các hạt cơ bản và không thể bị phá vỡ

B. chúng nhỏ hơn đáng kể so với nơtron hoặc proton

C. mức năng lượng của chúng là cố định và không thay đổi

D. chúng được giữ trong quỹ đạo bởi lực hút điện từ

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