K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

TL

Đố vui 2: What metal that was discovered end the primitive period?

- Copper and brass

HT

14 tháng 11 2021

right but u miss 1 more metal

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

What is the best title for the passage? 

A. The history of the photoflash 

B. Theories about how the eye reacts to light 

C. The technology of modern photography 

D. The dangers of using the early photoflash

1
7 tháng 1 2018

Đáp án A

Chủ đề về INVENTIONS

Tiêu đề chính của đoạn văn là gì?

A. Lịch sử của đèn nháy (đèn flash)

B. Các học thuyết về cách mà mắt phản ứng lại ánh sáng

C. Công nghệ chụp ảnh hiện đại

D. Những nguy hiểm của việc sử dụng đèn flash thủa ban đầu

Căn cứ vào các thông tin ở cả đoạn 1 và 2:

- “Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing magnesium wire and some oxygen-rich substance, such as potassium chlorate." (Đèn flash ngày nay được tạo ra hàng công nghệ tự động hóa, nhưng thủa sơ khai, khi lần đầu tiên được sử dụng vào năm 1864, nó chỉ là một túi giấy có chứa dây dẫn magiê và một số chất giàu oxy, như kali clorat.)

- “The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's." (Sự phát triển của đèn flash diễn ra chậm, các bóng đèn nháy, chứa dây dẫn làm bằng kim loại, như magiê hoặc nhóm, có khả năng bị đốt cháy trong môi trường chứa oxy tinh khiết ở áp suất thấp, chỉ được phát minh vào những năm 1920.)

Như vậy có thể thấy xuyên suốt bài đọc là lịch sử ra đời và phát triển của đèn flash => Do do, đáp án là A

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

According to the passage, what helps a flashbulb burn longer? 

A. thicker wire

B. more oxygen 

C. thinner glass 

D. continuous electricity

1
23 tháng 8 2019

Đáp án A

Theo bài văn, điều gì giúp cho bóng đèn flash có thể cháy lâu hơn?

A. dây dẫn dày hơn                                   B. nhiều Oxy hơn

C. kính mỏng hơn                                       D. điện thường xuyên

Căn cứ vào câu cuối của bài:

“A slightly bigger form of the metal will burn for a longer time.” (Một mẫu kim loại lớn hơn chút xíu sẽ cháy lâu hơn).

Trong suốt bài đọc, kim loại chính là dây dẫn trong bóng đèn flash.

17 tháng 7 2018

1. What do you call a fish that only cares about himself?

It's ''selfish''.

2. What is the word that everybody always says wrong?

It's the word ''WRONG''.

3. What has a neck but no head?

It's a bottle.

17 tháng 7 2018

1.selfish.

2.wrong.

3.bottle

The history of what we call cinema today began in the early 19th century. At that time, scientists discovered that when a sequence of still pictures was set in motion, they could give the feeling of movement. In the first two decades of its existence, the cinema developed rapidly. In those early days, films were little more than moving photographs, usually about one minute in length. By 1905, however, films were about five or ten minutes long. They used changes of scene and camera positions to...
Đọc tiếp

The history of what we call cinema today began in the early 19th century. At that time, scientists discovered that when a sequence of still pictures was set in motion, they could give the feeling of movement. In the first two decades of its existence, the cinema developed rapidly. In those early days, films were little more than moving photographs, usually about one minute in length. By 1905, however, films were about five or ten minutes long. They used changes of scene and camera positions to tell a story, with actors playing character parts. In the early 1910s, audiences were able to enjoy the first long films, but it was not until 1915 that the cinema really became an industry. From that time, film makers were prepared to make longer and better films and build special places where only films were shown. The cinema changed completely at the end of the 1920s. This was when sound was introduced. The change began in America and soon spread to the rest of the world. As the old silent films were being replaced by spoken ones on the screen, a new cinema form appeared, the musical cinema.
Cho e xin ý chính của đoạn anh văn đây với ạ

1
1 tháng 4 2022

A Brief of Cinema (Tóm tắt về điện ảnh)

dịch ra là thế này :

Sean bắt một con cá giải thưởng vào cuối tuần qua. Ông đã đi để đo lường nó nhưng nhận ra rằng người cai trị của ông là không đủ dài. Ông đã có thể đo đầu và phát hiện ra rằng nó là 9cm dài, sau đó ông đã đo đuôi và thấy rằng nó là chiều dài của đầu cộng với một nửa chiều dài của cơ thể. Nếu cơ thể là chiều dài của đầu cộng với đuôi, tổng chiều dài của cá là gì?

17 tháng 8 2016

ko phải người cai trị mà là cái thước kẻ của ông là ko đủ dài

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "it" in paragraph 2 refers to _____. 

A. oxygen

B. battery 

C. wire 

D. current

1
23 tháng 11 2019

Đáp án C

Từ "it” trong đoạn 2 đề cập đến

A. khí Oxy           B. Pin                    C. dây dẫn                    D. dòng điện

Căn cứ vào thông tin đoạn 2:

“The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it.” (Đèn flash được đốt sáng bằng cách xuyên thủng bóng đèn và cho phép oxy tiếp xúc với kim loại, khiến nó tự bốc cháy. Sau đó, những bóng đèn thắp sáng bởi một pin điện, pin này làm nóng dây dẫn bằng cách truyền một dòng điện nhỏ qua nó - tức là dây dẫn.)

Các đáp án còn lại có xuất hiện trong bài nhưng không chính xác nên ta

=> Do đó, đáp án là C

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

The word "momentarily"  in paragraph 2 is closet in meaning to ______. 

A. effortlessly

B. briefly 

C. electronically 

D. gradually

1
24 tháng 1 2018

Đáp án B

Từ “momentarily” trong đoạn 2 gần nghĩa với từ ___________.

A. effortlessly /'efətlisli/ (adv): một cách dễ dàng

B. briefly /'bri:fli/ (adv): một cách ngắn gọn

C. electronically /ilek'trɔnikli/ (adv): bằng điện tử

D. gradually /'grædjuəli/ (adv): dần dần, từ từ

Căn cứ vào ngữ cảnh đoạn 2:

“In each case, enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of Visible light.” (Trong mỗi trường hợp, một năng lượng vừa đủ được cung cấp để đốt cháy kim loại có thể oxy hóa trong giây lát để phát ra ánh sáng nóng trắng mà mắt thường có thể thấy được.)

=> Do đó, đáp án là B

Read the passage and mark the letter A, B, C or D to answer the following questions.Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture...
Đọc tiếp

Read the passage and mark the letter A, B, C or D to answer the following questions.

Most sources of illumination generate light over an appreciable period, and indeed if an object is lit for a very brief time (1ess that 1/25 second), the human eye will not react in time to see the object. A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting. Photoflash is now generated electronically, but the earliest form, first used in 1864, was a paper bag containing

magnesium wire and some oxygen-rich substance, such as potassium chlorate. When the bag was ignited, the metal burned with an intense flash. A contemporary observer reported that "this quite unsafe device seems to have done nothing worse that engulf the room in dense smoke and lead to pictures of dubious quality and odd poses.”

The evolution of the photoflash was slow, flashbulbs, containing fine wire made of a metal, such as magnesium or aluminum, capable of being ignited in an atmosphere of pure oxygen at low pressure, were introduced only in the 1920's. In the earliest type, the metal was separated from the oxygen by a thin glass bulb. The flash was fired by piercing the bulb and allowing the oxygen to come into contact with the metal, which ignited spontaneously. Later bulbs were fired by an electric battery, which heated the wire by passing a small current through it. Other combinations, such as the pairing of oxygen difluoride with zirconium, have also been used. In each case enough energy is given out to heat the oxidizable metal momentarily to a white hot emission of visible light. The smoke particles are so small that they cool rapidly; but since they are white, they contribute to the brilliance by reflecting the light from their still glowing neighbors. A slightly bigger form of the metal will burn for a longer time.

According to the passage, an advantage of using a photoflash is that it _____. 

A. can produce repeated bursts of light

B. intensities colors in photographs 

C. is short enough not to bother human eyes 

D. supplements existing lighting

1
20 tháng 10 2018

Đáp án D

Theo đoạn văn, một lợi ích của việc sử dụng đèn flash là nó _______.

A. có thể tạo ra những chùm sáng lặp đi lặp lại

B. tăng cường màu sắc trong các bức ảnh

C. đủ nhanh để không làm nheo mắt người được chụp ảnh

D. bổ sung ánh sáng hiện có

Dựa vào thông tin trong đoạn 1:

Tạm dịch: “A photographic emulsion - that is, a light-sensitive coating on photographic film, paper, or glass - will, however, record much shorter bursts of light. A photographic flash can therefore be used to capture high-speed movement on film as well as to correct deficiencies of the normal surrounding lighting." (Tuy nhiên, chất tráng phim dùng trong nhiếp ảnh - là một lớp phủ nhạy với ánh sáng trên phim ảnh, gidy hoặc thủy tinh - sẽ ghi lại những chùm ánh sáng ngắn hơn nhiều. Do đó, đèn flash chụp ảnh có thể được sử dụng để ghi lại chuyển động tốc độ cao trên phim cũng như điều chỉnh sự thiếu hụt của ánh sáng xung quanh)