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Tất cả Toán Vật lý Hóa học Sinh học Ngữ văn Tiếng anh Lịch sử Địa lý Tin học Công nghệ Giáo dục công dân Âm nhạc Mỹ thuật Tiếng anh thí điểm Lịch sử và Địa lý Thể dục Khoa học Tự nhiên và xã hội Đạo đức Thủ công Quốc phòng an ninh Tiếng việt Khoa học tự nhiên
Mua vip
BC
Bọ cạp nhỏ
22 tháng 3 2018

cho mình hỏi ta dùng on a helicopter hay in a helicopter?
#Tiếng anh lớp 7
2
TP
Thảo Phương
22 tháng 3 2018

Just thinking about why "in a helicopter" sounds better than "on a helicopter" it occurred to me that we most often say "on a bus" when in fact we actually travel "in a bus".

Đúng(0)
MT
Mai Thi Anh Hong
22 tháng 3 2018

Mình cũng nghĩ là ''in a helicopter''

Đúng(0)
S
Secret
21 tháng 7 2016
Read the passage and answer the multiple-choice questions.In 1863, the French writer Ponton D'Amecourt was the first person to create the word "helicopter" from the two words "helico" for spiral and "pter" for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He...
Đọc tiếp

Read the passage and answer the multiple-choice questions.

In 1863, the French writer Ponton D'Amecourt was the first person to create the word "helicopter" from the two words "helico" for spiral and "pter" for wings. The very first helicopter was invented by Paul Cornu in 1907, but it was not successful. French inventor, Etienne Oehmichen built and flew a helicopter one kilometer in 1924.

However, Igor Sikorsky is considered to be the father of helicopters not because he invented the first. He is called that because he invented the first successful helicopter, upon which further design were based. One of aviation's greatest designers, Russian born Igor Sikorsky began work on helicopters as early as 1910. By 1940, Igor Sikorsky's successful VS-300 had become the model for all modern helicopters of today. He also designed and built the first military helicopter.

Igor Sikorsky's helicopters had the control to fly safely forwards and backwards, up and down, and sideways. In 1958, Igor Sikorsky's company made the world's first helicopter that could land and take off from water. It could also float on the water.

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
#Tiếng anh lớp 8
2
PA
Phương An
21 tháng 7 2016

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
Đúng(0)
HR
Hannah Robert
21 tháng 7 2016

1. Igor Sikorsky invented the first helicopter in the world.

A. True              B. False              C. Not mentioned

2. Who created the word "helicopter"?

A. Igor SikorskyB. Paul CornuC. Ponton D'AmecourtD. Etienne Oehmichen

3. Why was Igor Sikorsky called the father of helicopter?

A. He invented the first helicopter.B. He began his work earlier than other inventors.C. He designed the first successful helicopter.D. He built the first military helicopter.

4. Igor Sikorsky designed VS-300 helicopter model _____?

A. before 1910B. before 1940C. after 1940D. after 1958

5. What made Igor Sikorsky's helicopters successful?

A. His helicopters can fly more than one kilometer.B. His helicopters can fly in all directions.C. His helicopters are cheaper to produce.D. His helicopters can be used as military helicopters

6. On the whole, the passage is about _____.

A. Igor Sikorsky's military helicoptersB. Igor Sikorsky's successful invention of helicopterC. a brief history of helicoptersD. the first helicopter in the world
Đúng(0)
DM
Dương Minh
29 tháng 11 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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

Why is it important that lift be equal on both sides of the helicopter shaft?

A. If there is more lift on one side, the helicopter will flip.

B. Equal lift means that the helicopter will be faster.

C. Dissymmetry of lift makes helicopters fly well.

D. It allows the rotor blade angles to be changed.
#Mẫu giáo
1
NH
Nguyen Hoang Hai
29 tháng 11 2017

Đáp án B

Đáp án nằm ở dòng 3, 4 và 5 đoạn 2: “Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.”

Đúng(0)
LQ
Lê Quỳnh Anh
19 tháng 4 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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

Why is it important that lift be equal on both sides of the helicopter shaft?

A. If there is more lift on one side, the helicopter will flip.

B. Equal lift means that the helicopter will be faster.

C. Dissymmetry of lift makes helicopters fly well.

D. It allows the rotor blade angles to be changed.
#Mẫu giáo
1
DH
Dương Hoàn Anh
19 tháng 4 2017

Đáp án B


Đáp án nằm ở dòng 3, 4 và 5 đoạn 2: “Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.”

Đúng(0)
LQ
Lê Quỳnh Anh
22 tháng 6 2019
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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

Why is it important that lift be equal on both sides of the helicopter shaft?

A. If there is more lift on one side, the helicopter will flip

B. Equal lift means that the helicopter will be faster

C. Dissymmetry of lift makes helicopters fly well

D. It allows the rotor blade angles to be changed
#Mẫu giáo
1
DH
Dương Hoàn Anh
22 tháng 6 2019

Đáp án B

Đáp án nằm ở dòng 3, 4 và 5 đoạn 2: “Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.”

Đúng(0)
LQ
Lê Quỳnh Anh
14 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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined 

B. perfected 

C. experienced 

D. taught
#Mẫu giáo
1
DH
Dương Hoàn Anh
14 tháng 9 2018

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Đúng(0)
DM
Dương Minh
17 tháng 10 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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined

B. perfected

C. experienced

D. taught
#Mẫu giáo
1
NH
Nguyen Hoang Hai
17 tháng 10 2018

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Đúng(0)
LQ
Lê Quỳnh Anh
12 tháng 9 2019
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 from 38 to 42. HISTORY OF THE HELICOPTER Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

The word “envisioned” in paragraph 1 is closet in meaning to _____.

A. imagined         

B. perfected          

C. experienced      

D. taught
#Mẫu giáo
1
DH
Dương Hoàn Anh
12 tháng 9 2019

Đáp án A

Envisioned ≈ imagined: mường tượng, hình dung

Đúng(0)
DM
Dương Minh
8 tháng 4 2019
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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

Why was “dissymmetry” important to the early pioneers of helicopter flight?

A. It was an effect that caused helicopter to crash.

B. It equalized lift on each side of the central shaft.

C. It allowed helicopters to lift from the ground.

D. It allowed the rotor blade angles to be altered.
#Mẫu giáo
1
NH
Nguyen Hoang Hai
8 tháng 4 2019

Đáp án A

Tại sao “tính không đối xứng” lại quan trọng với những chiếc máy bay trực thăng trước đây
Đáp án nằm ở dòng 3, 4 và 5 đoạn 2: “Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.”

Đúng(0)
LQ
Lê Quỳnh Anh
7 tháng 6 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 from 38 to 42.HISTORY OF THE HELICOPTERAlthough first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a...
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 from 38 to 42.

HISTORY OF THE HELICOPTER

Although first flight generally attributed to a fixed-wing aircraft, the helicopter actually represents the first style of flight envisioned by humans. The ancient Chinese developed a toy that rose upward when spun rapidly. As early as the mid-sixteenth century, the great Italian inventor Leonardo da Vinci had drawn a prototype for the machine that we now know as the helicopter.

Early in the twentieth century, a great deal of experimentation and revision was taking place with regard to helicopter flight. The well-known phrase “two steps forward and one step back” provided an apt descriptor for early flight development. Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.

On November 13, 1907, the French pioneer Paul Cornu made history by lifting a twin-rotor helicopter into the air for a few seconds without ground assistance. Several models followed without significance until in 1924 when another French pioneer, Etienne Oehmichen, became the first to fly a helicopter for one kilometer. It was a historic flight of 7 minutes and 40 seconds. By 1936, solutions have been found to many of the problems with helicopter flight.

With the introduction of the German Focke-Wulf Fw 61, the first practical helicopter became a reality.

 

Why was “dissymmetry” important to the early pioneers of helicopter flight?

A. It was an effect that caused helicopter to crash

B. It equalized lift on each side of the central shaft

C. It allowed helicopters to lift from the ground

D. It allowed the rotor blade angles to be altered
#Mẫu giáo
1
DH
Dương Hoàn Anh
7 tháng 6 2018

Đáp án A

Tại sao “tính không đối xứng” lại quan trọng với những chiếc máy bay trực thăng trước đây
Đáp án nằm ở dòng 3, 4 và 5 đoạn 2: “Uneven lift, known as dissymmetry, caused the early helicopters to flip over and confounded the inventors until the creation of the swash-plate; this allowed the rotor blade angles to be changed so that lift would be equal on each side of the shaft.”

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