Câu hỏi:
27/03/2020 1,082Read the followingpassage and mark the letter A, B, C or D onyour answer sheet to indicate the correct answer to each of the questions
Stellar Astronomy
Many parameters are used to describe a star. One of them is its temperature, which can be determined by simple observation; the color of a star and its temperature are related. Once the color of a star is identified, its temperature can be calculated through the use of scientific principles such as Wien’s Law.
There are different types of stars in the universe. For our purposes, we can classify them into two categories: variable and binary. Variable stars are those which show some degree of variability in their luminosity and magnitude. Luminosity refers to the amount of energy radiated by a star, while magnitude refers to its brightness. At time the degree of variability may be high, requiring a telescope with an equally high light- gathering power. This can be achieved by using a lens of large diameter, such as that of a reflecting telescope.
Binary stars are those found in pairs that revolve around a common center. The closest star to the sun, Proxima Centauri, is a binary star. To observe a binary star, the resolving power of a telescope - its ability to distinguish between two close objects having a small angular separation - must be very high.
Stellar astronomy is possible for a everyone, well beyond mere looking at the sky with the naked eye in order to identify constellations. With two basic of telescopes and rudimentary knowledge, much exploration can be achieved.
What is the topic of the passage?
Sách mới 2k7: Tổng ôn Toán, Lí, Hóa, Văn, Sử, Địa…. kỳ thi tốt nghiệp THPT Quốc gia 2025, đánh giá năng lực (chỉ từ 110k).
Quảng cáo
Trả lời:
Đáp án là A.
Các loại sao và làm thế nào để quan sát chúng. Đọc nội dung cả bài chúng ta dễ dàng chọn được đáp án này.
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 1:
Mark the letter A, B, C or D on your answer sheet to indicate the word or phrase that is CLOSEST in meaning to the underlinedpart in each of the following questions.
Local charity organizations benefited the fire victims
Câu 2:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Albert Emstein’s contributions to scientific theory were__________those of Galileo and Newton.
Câu 4:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
By the time you receive this letter, I__________for Japan.
Câu 5:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Ansel Adams was a landscape photographer__________photographs of the western United state show nature on a grand scale
Câu 6:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Artificial satellites provide data on atmospheric temperatures, solar radiation, and__________the earth’s surface.
Câu 7:
Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
A good friend will__________you when you’re having problems.
về câu hỏi!