[我的筆記]GWD4-Q35~Q37

[illuna]

In addition to conventional (=old) galaxies, the universe contains very dim galaxies that until recently (=new) went unnoticed by astronomers. (被太空人悄悄的解開) Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but (轉折語氣以後為主) tend to be much larger. Because (因果關係表原因) these galaxies’mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies. (new：areas變大 --> 星星數目不變(密度變小...整個galaxy亮度變暗) --> galaxy變大) Apparently these low-surface-brightness galaxies (=new) , as they are called, take much longer than conventional galaxies to condense their primordial gas and convert it to stars—that is, they evolve much more slowly. (new指出因為galaxy變大 --> 形成star的時間要更長) These galaxies may constitute an answer to the long-standing puzzle of the missing baryonic mass in the universe. (new的說法為B這件事帶來解答) Baryons—subatomic particles that are generally protons or neutrons—are the source of stellar, and therefore galactic, luminosity, and so their numbers can be estimated based on how luminous galaxies are. (B=測量galaxy亮度的方式) However (轉折語氣重點在後) , the amount of helium in the universe, as measured by spectroscopy, suggests that there are far more baryons in the universe than estimates based on galactic luminosity indicate. Astronomers have long speculated that the missing baryonic mass might eventually be discovered in intergalactic space or as some large population of galaxies that are difficult to detect.


文章結構：科學文章--description類型文章

[魚]

:-@

大家的效率都好高喔 !!!!

不行不行 ....我要跑快點 !

加油

[josephko]

這篇Q35請大家幫我說明一下
題目如下
Q35:
The primary purpose of the passage is to

A.describe a phenomenon and consider its scientific significance
B.contrast two phenomena and discuss a puzzling difference between them
C.identify a newly discovered phenomenon and explain its origins
D.compare two classes of objects and discuss the physical properties of each
E.discuss a discovery and point out its inconsistency with existing theory

答案是A
我覺得C比A好,

[davidlee0222]

C只講了前半
後半在講本發現的貢獻

[micht]

A.describe a phenomenon and consider its scientific significance

C.identify a newly discovered phenomenon and explain its
origins



粗體部分的地方有問題
文中沒有講 phenomenon(那個very dim galaxies) 是怎麼形成的吧

In addition to conventional
galaxies, the universe contains
very dim galaxies that until
Line recently went unnoticed by
(5)astronomers. Possibly as
numerous as conventional gal-
axies, these galaxies have the
same general shape and even
the same approximate number
(10)of stars as a common type of
conventional galaxy,

新發現


These galaxies may
constitute an answer to the long-
standing puzzle of the missing
baryonic mass in the universe.
Baryons—

新發現 能做什麼=> 劃線部份

[davidlee0222]

micht大大不好意思
小弟補充一下
有講現象為什麼形成
在您引言的下兩行
Because these galaxies’mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies

但因為只講了文章前半
因此不能代表全文主旨

[enim]

可以請問第37題嗎？

Q37.It can be inferred from the passage that which of the following is an accurate physical description of typical low-surface-brightness galaxies?

(A) They are large spiral galaxies containing fewer stars than do conventional galaxies.
(B) They are compact but very dim spiral galaxies.
(C) They are diffuse spiral galaxies that occupy a large volume of space.
(D) They are small, young spiral galaxies that contain a high proportion of primordial gas.
(E) They are large, dense spirals with low luminosity.

ans:C


Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but tend to be much larger. Because these galaxies’mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies. Apparently these low-surface-brightness galaxies, as they are called, take much longer than conventional galaxies to condense their primordial gas and convert it to stars—that is, they evolve much more slowly.

我選A...根據這一段話，我覺得A也可以耶！

還請大大開示一下...謝謝

[cynthiachan]

(A) They are large spiral galaxies containing fewer stars than do conventional galaxies.
(C) They are diffuse spiral galaxies that occupy a large volume of space.

Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but tend to be much larger.

文章應該是指spiral 會比 conventional galaxy大 。所以選C
答案A的意思是拿galaxies的大小來比，large 修飾 spiral galaxies, 而非spiral 更重要的是the same approximate number of stars as a common type of
conventional galaxy

個人淺見~

[FionaV]

請問Q36
The author mentions the fact that baryons are the source of stars' luminosity primarily in order to explain

A. how astronomers determine that some galaxies contain fewer stars per unit volume than do others
B. how astronomers are able to calculate the total luminosity of a galaxy
C. why astronomers can use galactice luminosity to estimate baryonic mass
D. why astronomers' estimates of baryonic mass based on galactic luminosity are more reliable than those based on spectroscopic studies of helium
E. how astronomers know bright galaxies contain more baryons than do dim galaxies

這題我所有的選項都不是很懂 更不知道A是怎麼來的 可以幫幫我嗎~~

[stilalala]

(A) They are large spiral galaxies containing fewer stars than do conventional galaxies.
(C) They are diffuse spiral galaxies that occupy a large volume of space.

Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but tend to be much larger.

文章應該是指spiral 會比 conventional galaxy大 。所以選C
答案A的意思是拿galaxies的大小來比，large 修飾 spiral galaxies, 而非spiral 更重要的是the same approximate number of stars as a common type of
conventional galaxy

個人淺見~

有一個小小的疑問
在line11 , conventional galaxy , the spiral ,....
spiral是galaxy的同位語嗎??
如果是的話galaxy 與 spiral應該是一樣的??

同意您的解法,
dim galaxy的數量並沒有比conventinal的少
只是spiral 比較大
所以 total star / volume of spiral 比較小
所以(a)fewer stars 不對
(b) (e) compact , denSe不對
(c)small錯'

敬請指教

[stilalala]

請問Q36
The author mentions the fact that baryons are the source of stars' luminosity primarily in order to explain

A. how astronomers determine that some galaxies contain fewer stars per unit volume than do others
B. how astronomers are able to calculate the total luminosity of a galaxy
C. why astronomers can use galactice luminosity to estimate baryonic mass
D. why astronomers' estimates of baryonic mass based on galactic luminosity are more reliable than those based on spectroscopic studies of helium
E. how astronomers know bright galaxies contain more baryons than do dim galaxies

這題我所有的選項都不是很懂 更不知道A是怎麼來的 可以幫幫我嗎~~

答案應該是c吧

Baryons—subatomic particles that are generally protons or neutrons—are the source of stellar, and therefore galactic, luminosity, and so their numbers can be estimated based on how luminous galaxies are.文章說明”B”是stellar的source,…..然後注意劃線的部份 “therefore..and ..so”
顯示出說明”B”的目的是要表明,可以利用”亮度”來衡量”B”的數量
即如(C)所言
(A) 星星的數量是在第一段,我想是定位錯了
(B) 這句話的作用是如(C)而言,而不是要說明如何可以衡量亮度吧
文章也沒有說要計算亮度的方法 ,也就是根本沒說明”HOW”
(C) 正確
(D)沒有說用亮度衡量比較可信吧, 相反的,用spectroscopic估計”b”的數量,
比用亮度衡量的多,這就是所謂的puzzle,代表利用亮度,並沒有辦法估計出”b”該有的數量
這也就是文章為何要說發現這種新的galaxy有用的原因,因為這種比較暗的星星就是之前被忽略的
(E)我覺得這個好像就是FACT吧,這個不是很確定
請指教

[nexxt0722]

36題的答案應該是C,stilalala的說明相當清楚,贊同!

[nexxt0722]

Q37.It can be inferred from the passage that which of the following is an accurate physical description of typical low-surface-brightness galaxies?

(A) They are large spiral galaxies containing fewer stars than do conventional galaxies.
(B) They are compact but very dim spiral galaxies.
(C) They are diffuse spiral galaxies that occupy a large volume of space.
(D) They are small, young spiral galaxies that contain a high proportion of primordial gas.
(E) They are large, dense spirals with low luminosity.

文中這二句話可以解決問題

Possibly as numerous as conventional galaxies, these galaxies have the same general shape
and even the same approximate number of stars as a common type of conventional galaxy,
the spiral, but tend to be much larger


Because these galaxies’mass is spread out over larger areas,
they have far fewer stars per unit volume than do conventional galaxies.

各選項的錯誤如下
(A) fewer stars
(B) compact
(D) small
(E) dense

[Jen-Cheng]

"These galaxies may constitute an answer to the long-standing puzzle of the missing baryonic mass in the universe."

請問一下: 這邊的answer 是指，在dim galaxies 裡終於找到 missing baryonic嗎?

[mandy-lo]

GWD4-Q35~Q37

To Jen-Cheng 大大:


這句話中的answer應該是表示可以answer消失的B mass這件事,因為B可用來決定亮度的

至於Q36， stilalala大大的解說相當清楚,再補充一下E選:
Q36問的是作者提到這個事實的主要目的是什麼?
The author mentions the fact that baryons are the source of stars' luminosity primarily in order to explain
E. how astronomers know bright galaxies contain more baryons than do dim galaxies
E選僅是事實陳述非作者的目的

呵呵…. 若解說有誤,歡迎指正