Câu hỏi: Read the following passage and mark the letter A, B, C or D on you answer sheet to indicate the correct answer to each of thequestions.
SCIENTIFIC DISCOVERIES
A satellite is best understood as a projectile, or an object that has only one force acting on gravity. Technically speaking, anything that crosses the Karman Line at an altitude of kilometers (62 miles) is considered in space. However, a satellite needs to be going fast — at least 8 km (5 miles) a second - to stop from falling back down to Earth immediately.
If a satellite is traveling fast enough, it will perpetually "fall" toward Earth, but the Earth's curvature means that the satellite will fall around our planet instead of crashing back on the surface. Satellites that travel closer to Earth are at risk of falling because the drag of atmospheric molecules will slow the satellites down. Those that orbit farther away from Earth have fewer molecules to contend with.
There are several accepted "zones" of orbits around the Earth. One is called low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles). This is the zone where the ISS orbits and where the space shuttle used to do its work. In fact, all human missions except for the Apollo flights to the moon took place in this zone. Most satellites also work in this zone.
Geostationary or geosynchronous orbit is the best spot for communications satellites to use, however. This is a zone above Earth's equator at an altitude of 35,786 km (22,236 mi). At this altitude, the rate of "fall" around the Earth is about the same as Earth's rotation, which allows the satellite to stay above the same spot on Earth almost constantly. The satellite thus keeps a perpetual connection with a fixed antenna on the ground, allowing for reliable communications. When geostationary satellites reach the end of their life, protocol dictates they're moved out of the way for a new satellite to take their place. That's because there is only so much room, or so many "slots" in that orbit, to allow the satellites to operate without interference.
While some satellites are best used around the equator, others are better suited to more polar orbits - those that circle the Earth from pole to pole so that their coverage zones include the north and south poles. Examples of polar-orbiting satellites include weather satellites and reconnaissance satellites.
(Source: https://www.space.com/24839-satellites.html)
Which of the following is NOT true according to the passage?
A. satellite needs to be going fast - at least 8 km (5 miles) a second.
B. Satellites that travel closer to Earth contend with drag of more atmospheric molecules.
C. Satellites keep a perpetual connection with a fixed antenna on the ground
D. The Apollo flights to the moon took place in low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles).
SCIENTIFIC DISCOVERIES
A satellite is best understood as a projectile, or an object that has only one force acting on gravity. Technically speaking, anything that crosses the Karman Line at an altitude of kilometers (62 miles) is considered in space. However, a satellite needs to be going fast — at least 8 km (5 miles) a second - to stop from falling back down to Earth immediately.
If a satellite is traveling fast enough, it will perpetually "fall" toward Earth, but the Earth's curvature means that the satellite will fall around our planet instead of crashing back on the surface. Satellites that travel closer to Earth are at risk of falling because the drag of atmospheric molecules will slow the satellites down. Those that orbit farther away from Earth have fewer molecules to contend with.
There are several accepted "zones" of orbits around the Earth. One is called low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles). This is the zone where the ISS orbits and where the space shuttle used to do its work. In fact, all human missions except for the Apollo flights to the moon took place in this zone. Most satellites also work in this zone.
Geostationary or geosynchronous orbit is the best spot for communications satellites to use, however. This is a zone above Earth's equator at an altitude of 35,786 km (22,236 mi). At this altitude, the rate of "fall" around the Earth is about the same as Earth's rotation, which allows the satellite to stay above the same spot on Earth almost constantly. The satellite thus keeps a perpetual connection with a fixed antenna on the ground, allowing for reliable communications. When geostationary satellites reach the end of their life, protocol dictates they're moved out of the way for a new satellite to take their place. That's because there is only so much room, or so many "slots" in that orbit, to allow the satellites to operate without interference.
While some satellites are best used around the equator, others are better suited to more polar orbits - those that circle the Earth from pole to pole so that their coverage zones include the north and south poles. Examples of polar-orbiting satellites include weather satellites and reconnaissance satellites.
(Source: https://www.space.com/24839-satellites.html)
Which of the following is NOT true according to the passage?
A. satellite needs to be going fast - at least 8 km (5 miles) a second.
B. Satellites that travel closer to Earth contend with drag of more atmospheric molecules.
C. Satellites keep a perpetual connection with a fixed antenna on the ground
D. The Apollo flights to the moon took place in low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles).
Kiến thức: Đọc hiểu
A. Vệ tinh cần đi nhanh - ít nhất là 8 km (5 dặm) một giây
B. Các vệ tinh đi gần Trái đất phải đối mặt với lực cản của nhiều phân tử khí quyển hơn
C. Vệ tinh giữ kết nối vĩnh viễn với một ăng-ten cố định trên mặt đất
D. Các chuyến bay Apollo lên mặt trăng đã diễn ra trong Trái Đất trên quỹ đạo thấp, kéo dài từ khoảng 160 đến 2.000 km (khoảng 100 đến 1.250 dặm).
Tạm dịch: One is called low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles). This is the zone where the ISS orbits and where the space shuttle used to do its work. In fact, all human missions except for the Apollo flights to the moon took place in this zone
(Một cái được gọi là trái đất quỹ đạo thấp, kéo dài từ khoảng 160 đến 2.000 km (khoảng 100 đến 1.250 dặm). Đây là khu vực mà ISS quay quanh và nơi tàu con thoi từng làm công việc của mình. Trên thực tế, tất cả các sứ mệnh của loài người ngoại trừ các chuyến bay của Apollo lên mặt trăng đều diễn ra trong khu vực này)
A. Vệ tinh cần đi nhanh - ít nhất là 8 km (5 dặm) một giây
B. Các vệ tinh đi gần Trái đất phải đối mặt với lực cản của nhiều phân tử khí quyển hơn
C. Vệ tinh giữ kết nối vĩnh viễn với một ăng-ten cố định trên mặt đất
D. Các chuyến bay Apollo lên mặt trăng đã diễn ra trong Trái Đất trên quỹ đạo thấp, kéo dài từ khoảng 160 đến 2.000 km (khoảng 100 đến 1.250 dặm).
Tạm dịch: One is called low-Earth-orbit, which extends from about 160 to 2,000 km (about 100 to 1,250 miles). This is the zone where the ISS orbits and where the space shuttle used to do its work. In fact, all human missions except for the Apollo flights to the moon took place in this zone
(Một cái được gọi là trái đất quỹ đạo thấp, kéo dài từ khoảng 160 đến 2.000 km (khoảng 100 đến 1.250 dặm). Đây là khu vực mà ISS quay quanh và nơi tàu con thoi từng làm công việc của mình. Trên thực tế, tất cả các sứ mệnh của loài người ngoại trừ các chuyến bay của Apollo lên mặt trăng đều diễn ra trong khu vực này)
Đáp án D.