Astronomers studying

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Astronomers studying

by akhpad » Fri Aug 20, 2010 6:32 am
Source: VeritasPrep

Astronomers studying the history of the universe use equipment sensitive to different wavelengths of light, which were produced at different points in time. As the universe expanded over time, the light waves traveling through it expanded as well. Therefore, visible light produced by the earliest galaxies reaches Earth as longer infrared waves. Clearly, then, the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves.

Which of the following is an assumption on which this argument depends?

A: Microwaves are more likely than infrared waves to emit visible light.
B: Because the universe continues to expand in size, astronomers must develop new equipment to measure the light waves traveling through it.
C: Hydrogen atoms played an important role in the creation of the earliest galaxies.
D: The size of light waves directly correlates to the amount of visible light produced by the waves.
E: The clouds of hydrogen atoms preceding early galaxies emitted visible light.

OA: E

I am confused on "the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves."
Last edited by akhpad on Fri Aug 20, 2010 8:18 pm, edited 2 times in total.
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by FightWithGMAT » Fri Aug 20, 2010 7:38 am
akhp77 wrote:Astronomers studying the history of the universe use equipment sensitive to different wavelengths of light, which were produced at different points in time. As the universe expanded over time, the light waves traveling through it expanded as well. Therefore, visible light produced by the earliest galaxies reaches Earth as longer infrared waves. Clearly, then, the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves.

Which of the following is an assumption on which this argument depends?

A: Microwaves are more likely than infrared waves to emit visible light.
B: Because the universe continues to expand in size, astronomers must develop new equipment to measure the light waves traveling through it.
C: Hydrogen atoms played an important role in the creation of the earliest galaxies.
D: The size of light waves directly correlates to the amount of visible light produced by the waves.
E: The clouds of hydrogen atoms preceding early galaxies emitted visible light.

I am confused on "the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves."
Is OA E?

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by Gurpinder » Fri Aug 20, 2010 8:14 am
I would say (D).


Whats the OA?

"the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves."

I am guessing you are confused about the meaning. All this is saying is that the group of hydrogen atoms that were there before these galaxies will now be seen as longer microwaves.
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by SeemaSkl » Fri Aug 20, 2010 9:51 am
IMO E.

Argument basically says older the object, longer will be the wavelength of light when it reaches the instrument. Since hydrogen clouds are older than the galaxy, their wavelength will be more. But this is possible only if they produce light like the galaxies. If they don't, the argument falls apart. Therefor this is the assumption.

D basically repeats the premise in the argument.

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by loving.achin » Fri Aug 20, 2010 10:53 am
'D'

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by debmalya_dutta » Fri Aug 20, 2010 5:53 pm
My pick is E
Contenders , for me , were only D & E

Conclusion was
"the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves"

So my reasoning was -
so , these hydrogen atom will be detectable i.e so that means these emit some sort of visible light and only then can they be detectable as even longer microwaves . The stimulus says that the more time the light waves travel , the longer the the light waves will be ... since the clouds of hydrogen atoms preceded the galaxies , they will have longer wavelengths. ....But they will only be detected if they are visible ....
akhp77 wrote:Source: VeritasPrep

Astronomers studying the history of the universe use equipment sensitive to different wavelengths of light, which were produced at different points in time. As the universe expanded over time, the light waves traveling through it expanded as well. Therefore, visible light produced by the earliest galaxies reaches Earth as longer infrared waves. Clearly, then, the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves.

Which of the following is an assumption on which this argument depends?

A: Microwaves are more likely than infrared waves to emit visible light.
B: Because the universe continues to expand in size, astronomers must develop new equipment to measure the light waves traveling through it.
C: Hydrogen atoms played an important role in the creation of the earliest galaxies.
D: The size of light waves directly correlates to the amount of visible light produced by the waves.
E: The clouds of hydrogen atoms preceding early galaxies emitted visible light.

I am confused on "the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves."
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by vijaynaik » Fri Aug 20, 2010 6:03 pm
I will go with E.

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by akhpad » Fri Aug 20, 2010 8:31 pm
I confused to understand this part.
debmalya_dutta wrote: Conclusion was
"the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves"
What is the use of "preceded" and "detected"?

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by debmalya_dutta » Fri Aug 20, 2010 9:20 pm
akhp77 wrote:I confused to understand this part.
debmalya_dutta wrote: Conclusion was
"the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves"
What is the use of "preceded" and "detected"?
Sorry..am not sure what your question is.... did you mean to ask what the 2 words mean in this context?
"the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves"
"the clouds of hydrogen atoms that existed before these early galaxies will be spotted /located/observed/found as even longer microwaves"
in other words
1. the clouds of hydrogen atoms existed before these early galaxies AND
2. the clouds of hydrogen atoms will be found as even longer microwaves
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by diebeatsthegmat » Sun Aug 22, 2010 6:19 am
akhp77 wrote:Source: VeritasPrep

Astronomers studying the history of the universe use equipment sensitive to different wavelengths of light, which were produced at different points in time. As the universe expanded over time, the light waves traveling through it expanded as well. Therefore, visible light produced by the earliest galaxies reaches Earth as longer infrared waves. Clearly, then, the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves.

Which of the following is an assumption on which this argument depends?

A: Microwaves are more likely than infrared waves to emit visible light.
B: Because the universe continues to expand in size, astronomers must develop new equipment to measure the light waves traveling through it.
C: Hydrogen atoms played an important role in the creation of the earliest galaxies.
D: The size of light waves directly correlates to the amount of visible light produced by the waves.
E: The clouds of hydrogen atoms preceding early galaxies emitted visible light.

OA: E

I am confused on "the clouds of hydrogen atoms that preceded these early galaxies will be detected as even longer microwaves."
carefully read the last sentences from "therefore.....blah blah" you will see the answer choice must be E