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# Virtually everything astronomers known about objects outside

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Director
Joined: 04 Jan 2008
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02 Mar 2009, 12:43
3
KUDOS
1
This post was
BOOKMARKED
Question 1
00:00

Question Stats:

48% (02:07) correct 52% (02:12) wrong based on 93

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Question 2
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74% (00:26) correct 26% (01:12) wrong based on 87

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Question 3
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64% (00:28) correct 36% (00:43) wrong based on 85

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Question 4
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90% (00:23) correct 10% (00:20) wrong based on 83

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Question 5
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76% (00:37) correct 24% (00:15) wrong based on 80

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Question 6
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83% (00:12) correct 18% (00:10) wrong based on 80

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77% (00:19) correct 23% (00:22) wrong based on 83

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78% (00:30) correct 23% (00:41) wrong based on 80

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Question 9
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60% (00:47) correct 40% (01:07) wrong based on 80

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Quote:
Part of New RC Series- Please check this link for more questions

Virtually everything astronomers known about objects outside the solar system is based on the detection of photons—quanta of electromagnetic radiation. Yet there is another form of radiation that permeates the universe: neutrinos. With (as its name implies) no electric charge, and negligible mass, the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe, even traversing substantial aggregations of matter, without being absorbed or even deflected. Neutrinos can thus escape from regions of space where light and other kinds of electromagnetic radiation are blocked by matter. Furthermore, neutrinos carry with them information about the site and circumstances of their production: therefore, the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe.
But how can scientists detect a particle that interacts so infrequently with other matter? Twenty-five years passed between Pauli’s hypothesis that the neutrino existed and its actual detection: since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. But a neutrino telescope, capable of detecting cosmic neutrinos, is difficult to construct. No apparatus can detect neutrinos unless it is extremely massive, because great mass is synonymous with huge numbers of nucleons (neutrons and protons), and the more massive the detector, the greater the probability of one of its nucleon’s reacting with a neutrino. In addition, the apparatus must be sufficiently shielded from the interfering effects of other particles.

Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean. Named DUMAND, for Deep Underwater Muon and Neutrino Detector, the project calls for placing an array of light sensors at a depth of five kilometers under the ocean surface. The detecting medium is the seawater itself: when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors. The five kilometers of seawater above the sensors will shield them from the interfering effects of other high-energy particles raining down through the atmosphere.

The strongest motivation for the DUMAND project is that it will exploit an important source of information about the universe. The extension of astronomy from visible light to radio waves to x-rays and gamma rays never failed to lead to the discovery of unusual objects such as radio galaxies, quasars, and pulsars. Each of these discoveries came as a surprise. Neutrino astronomy will doubtless bring its own share of surprises.
1. Which of the following titles best summarizes the passage as a whole?
(A) At the Threshold of Neutrino Astronomy
(B) Neutrinos and the History of the Universe
(C) The Creation and Study of Neutrinos
(D) The DUMAND System and How It Works
(E) The Properties of the Neutrino

[Reveal] Spoiler:
A

2. With which of the following statements regarding neutrino astronomy would the author be most likely to agree?
(A) Neutrino astronomy will supersede all present forms of astronomy.
(B) Neutrino astronomy will be abandoned if the DUMAND project fails.
(C) Neutrino astronomy can be expected to lead to major breakthroughs in astronomy.
(D) Neutrino astronomy will disclose phenomena that will be more surprising than past discoveries.
(E) Neutrino astronomy will always be characterized by a large time lag between hypothesis and experimental confirmation.

[Reveal] Spoiler:
C

3. In the last paragraph, the author describes the development of astronomy in order to
(A) suggest that the potential findings of neutrino astronomy can be seen as part of a series of astronomical successes
(B) illustrate the role of surprise in scientific discovery
(C) demonstrate the effectiveness of the DUMAND apparatus in detecting neutrinos
(D) name some cosmic phenomena that neutrino astronomy will illuminate
(E) contrast the motivation of earlier astronomers with that of the astrophysicists working on the DUMAND project

[Reveal] Spoiler:
A

4. According to the passage, one advantage that neutrinos have for studies in astronomy is that they
(A) have been detected for the last twenty-five years
(B) possess a variable electric charge
(C) are usually extremely massive
(D) carry information about their history with them
(E) are very similar to other electromagnetic particles

[Reveal] Spoiler:
D

5. According to the passage, the primary use of the apparatus mentioned in lines 24-32 would be to
(A) increase the mass of a neutrino
(B) interpret the information neutrinos carry with them
(C) study the internal structure of a neutrino
(D) see neutrinos in distant regions of space
(E) detect the presence of cosmic neutrinos

[Reveal] Spoiler:
E

6. The passage states that interactions between neutrinos and other matter are
(A) rare
(B) artificial
(C) undetectable
(D) unpredictable
(E) hazardous

[Reveal] Spoiler:
A

7. The passage mentions which of the following as a reason that neutrinos are hard to detect?
(A) Their pervasiveness in the universe
(B) Their ability to escape from different regions of space
(C) Their inability to penetrate dense matter
(D) The similarity of their structure to that of nucleons
(E) The infrequency of their interaction with other matter

[Reveal] Spoiler:
E

8. According to the passage, the interaction of a neutrino with other matter can produce
(A) particles that are neutral and massive
(B) a form of radiation that permeates the universe
(C) inaccurate information about the site and circumstances of the neutrino’s production
(D) charged particles and light
(E) a situation in which light and other forms of electromagnetic radiation are blocked

[Reveal] Spoiler:
D

9. According to the passage, one of the methods used to establish the properties of neutrinos was
(A) detection of photons
(B) observation of the interaction of neutrinos with gamma rays
(C) observation of neutrinos that were artificially created
(D) measurement of neutrinos that interacted with particles of seawater

[Reveal] Spoiler:
C

Lets Practice 3 RCs per day
I am posting one RC/day
if response is good, will post more
no OE in this passage.only OAs.
Even if i get one response I will post the OAs-promise
so friends
here you go
[Reveal] Spoiler: Question #1 OA
[Reveal] Spoiler: Question #2 OA
[Reveal] Spoiler: Question #3 OA
[Reveal] Spoiler: Question #4 OA
[Reveal] Spoiler: Question #5 OA
[Reveal] Spoiler: Question #6 OA
[Reveal] Spoiler: Question #7 OA
[Reveal] Spoiler: Question #8 OA
[Reveal] Spoiler: Question #9 OA

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Last edited by Gnpth on 12 Oct 2017, 14:24, edited 3 times in total.
OA not Provided & improper formatting

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02 Mar 2009, 21:50
I am signing up. Just like the good old ad, am egg a day keeps the doctor away, 3 RC's a day gets you closer to the GMAT target.

Here is what I got.

I feel that passages as long as this one are atypical of GMAT.

How much time do you think is good enough for this passage?

Any ways, if this is LSAT stuff, its good to do because it makes GMAT RC easier.

B T W, I took a guess on Q 5, which had line numbers mentioned in Q and the Q did not have the appropriate lines underlined. I hope I am right on that.

B,C,A,D,E,A,E,D,C

I was really torn on the first Q and spent a lot of time. Nothing made sense to me. By POE I arrived at B.

Now lets get to the OA's/OE's and discussion.

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Director
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02 Mar 2009, 22:09
Now since I know how the Real Qs look like ..promise you all that I will try to post GMAT-like RCs(theme wise-astronomy,archaeology,paleontology,World War II, Climate Change, paintings etc)
this one is not from LSAT category

Q 1 was most difficult to guess.I got 5/9 right.Poor I must say
I believe one can take 2 Mins/Qs..say 16-18 Mins for this 9 Q passage(becoz its not a tough passage)
with practice, we should bring done the time taken/passage
every 10-20 seconds we save will help us in CR/SC

will post the OAs soon
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03 Mar 2009, 10:07
Nitya.....dat is a wonderful thing u hv started. I alw thought dat we adenough practice of SC and CR. but RC was rarely practiced.I hope now 3 RCs will be posted since u got the replies
Needless 2 say, +1 frm me

now my ans:
1 A
2 C
3 A
4 D
5 E
6 A
7 E
8 D
9 C

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03 Mar 2009, 10:29
Thanks for kind words.
you got all

posting the RC of 4 march soon

ritula wrote:
Nitya.....dat is a wonderful thing u hv started. I alw thought dat we adenough practice of SC and CR. but RC was rarely practiced.I hope now 3 RCs will be posted since u got the replies
Needless 2 say, +1 frm me

now my ans:
1 A
2 C
3 A
4 D
5 E
6 A
7 E
8 D
9 C

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03 Mar 2009, 11:31
1 is A?

At the threshold of N A?

What does the word threshold mean here in this context? Long due?? Is that what it means?

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03 Mar 2009, 19:18
I got it wrong too
Q1's ans is most confusing

if anyone can throw light

icandy wrote:
1 is A?

At the threshold of N A?

What does the word threshold mean here in this context? Long due?? Is that what it means?

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03 Mar 2009, 22:21
Threshold means "The starting point for a new state or experience"

In the passage, it has been stated that scientists have proposed the concept of neutrinos. here is the line
"Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean"
Also the passage concludes with "Neutrino astronomy will doubtless bring its own share of surprises". Hence the name "At the threshold of N A" is most suitable.

icandy wrote:
1 is A?

At the threshold of N A?

What does the word threshold mean here in this context? Long due?? Is that what it means?

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03 Mar 2009, 23:08
By POE, I also had to choose from option A and B and finally chose option B. However, after seeing the OA, A does make sense.

The passage does not talk about History of universe with respect to Nutrino. In fact, it explains hos Nutrino Astronomy and expects surprises. Hence, an answer choice with "Nutrono Astronomy" will be the most correct answer. Here, between A and B, A contains this.

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15 Apr 2009, 10:05
Can any body tell why E is wrong in q3.

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12 May 2009, 13:36

1) C
2) C
3) E
4) D
5) E
6) A
7) E
8) D
9) C

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25 Aug 2009, 05:21
I guess this one is easy .. took 11 mins.

1 a
2 d //wrong ...it's C I don't how I missed it..easy one
3 a
4 d
5 e
6 a
7 e
8 d
9 c

corrects : 8/9

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25 Aug 2009, 10:46
8/9 17 Min. I feel this one had many questions that were Specific to the passage type...no Main Idea, what did the author mean, etc

2. I missed...I had it down to C and E and went with E based on the understanding that the passage said it was discovered 25 years ago but with no real testing. So I interpreted the answer choice but I guess the answer choice is relative.

3. Was tricky and was down to A and C...but after POE I went with A

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16 Aug 2011, 00:29
Hi,

Amar
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Test Description_______Date____Total___Quant_____ Verbal
GMAT PREP1_____________________610
GMAX online test 1____29.07.2011__540_____43________19
MGMAT CAT 1_________03.09.2011__580____42________28
MGMAT CAT 2_________02.10.2011__690____48________36
GMAX online test 2_____16.10.2011__640____48________32
MGMAT CAT 3_________23.11.2011__670____47________34
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MGMAT CAT 4_________06.11.2011__690____48________36
MGMAT CAT 5_________13.11.2011__660____46________34
MGMAT CAT 6_________19.11.2011__680____51________33
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GMAT Exam___________24.11.2011__690____50________34

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03 Aug 2013, 10:35

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06 Aug 2013, 18:28
need explanation for QUESTION 1
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06 Aug 2013, 20:03
2
KUDOS
Virtually everything astronomers known about objects outside the solar system is based on the detection of photons—quanta of electromagnetic radiation. Yet there is another form of radiation that permeates the universe: neutrinos. With (as its name implies) no electric charge, and negligible mass, the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe, even traversing substantial aggregations of matter, without being absorbed or even deflected. Neutrinos can thus escape from regions of space where light and other kinds of electromagnetic radiation are blocked by matter. Furthermore, neutrinos carry with them information about the site and circumstances of their production: therefore, the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe.

But how can scientists detect a particle that interacts so infrequently with other matter? Twenty-five years passed between Pauli’s hypothesis that the neutrino existed and its actual detection: since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators and studied under neutrino microscopes. But a neutrino telescope, capable of detecting cosmic neutrinos, is difficult to construct. No apparatus can detect neutrinos unless it is extremely massive, because great mass is synonymous with huge numbers of nucleons (neutrons and protons), and the more massive the detector, the greater the probability of one of its nucleon’s reacting with a neutrino. In addition, the apparatus must be sufficiently shielded from the interfering effects of other particles.

Fortunately, a group of astrophysicists has proposed a means of detecting cosmic neutrinos by harnessing the mass of the ocean. Named DUMAND, for Deep Underwater Muon and Neutrino Detector, the project calls for placing an array of light sensors at a depth of five kilometers under the ocean surface. The detecting medium is the seawater itself: when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light that can be detected by the sensors. The five kilometers of seawater above the sensors will shield them from the interfering effects of other high-energy particles raining down through the atmosphere.

The strongest motivation for the DUMAND project is that it will exploit an important source of information about the universe. The extension of astronomy from visible light to radio waves to x-rays and gamma rays never failed to lead to the discovery of unusual objects such as radio galaxies, quasars, and pulsars. Each of these discoveries came as a surprise. Neutrino astronomy will doubtless bring its own share of surprises.
1. Which of the following titles best summarizes the passage as a whole?
(A) At the Threshold of Neutrino Astronomy
(B) Neutrinos and the History of the Universe
(C) The Creation and Study of Neutrinos
the passage is not about creation of Neutrino, but about detecting neutrino
(D) The DUMAND System and How It Works
it is the one that best summerizes the passage
(E) The Properties of the Neutrino
[Reveal] Spoiler:
A

2. With which of the following statements regarding neutrino astronomy would the author be most likely to agree?
(A) Neutrino astronomy will supersede all present forms of astronomy.
(B) Neutrino astronomy will be abandoned if the DUMAND project fails.
(C) Neutrino astronomy can be expected to lead to major breakthroughs in astronomy.
the detection of cosmic neutrinos could provide new information about a wide variety of cosmic phenomena and about the history of the universe
therefore, its expected to lead to major breakthroughs in astronomy

(D) Neutrino astronomy will disclose phenomena that will be more surprising than past discoveries.
(E) Neutrino astronomy will always be characterized by a large time lag between hypothesis and experimental confirmation.
[Reveal] Spoiler:
C

3. In the last paragraph, the author describes the development of astronomy in order to
(A) suggest that the potential findings of neutrino astronomy can be seen as part of a series of astronomical successes
Neutrino astronomy will doubtless bring its own share of surprises
correct!

(B) illustrate the role of surprise in scientific discovery
(C) demonstrate the effectiveness of the DUMAND apparatus in detecting neutrinos
(D) name some cosmic phenomena that neutrino astronomy will illuminate
(E) contrast the motivation of earlier astronomers with that of the astrophysicists working on the DUMAND project
[Reveal] Spoiler:
A

4. According to the passage, one advantage that neutrinos have for studies in astronomy is that they
(A) have been detected for the last twenty-five years
(B) possess a variable electric charge
(C) are usually extremely massive
(D) carry information about their history with them
neutrinos carry with them information about the site and circumstances of their production
correct!

(E) are very similar to other electromagnetic particles
[Reveal] Spoiler:
D

5. According to the passage, the primary use of the apparatus mentioned in lines 24-32 would be to
(A) increase the mass of a neutrino
(B) interpret the information neutrinos carry with them
(C) study the internal structure of a neutrino
(D) see neutrinos in distant regions of space
(E) detect the presence of cosmic neutrinos
No apparatus can detect neutrinos unless it is extremely massive
correct!
[Reveal] Spoiler:
E

6. The passage states that interactions between neutrinos and other matter are
(A) rare
the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe...
(B) artificial
(C) undetectable
(D) unpredictable
(E) hazardous
[Reveal] Spoiler:
A

7. The passage mentions which of the following as a reason that neutrinos are hard to detect?
(A) Their pervasiveness in the universe
(B) Their ability to escape from different regions of space
(C) Their inability to penetrate dense matter
(D) The similarity of their structure to that of nucleons
(E) The infrequency of their interaction with other matter
the neutrino interacts with other particles so rarely that a neutrino can cross the entire universe., even traversing substantial aggregations of matter, without being absorbed or even deflected. .

a particle that interacts so infrequently with other matter?
[Reveal] Spoiler:
E

8. According to the passage, the interaction of a neutrino with other matter can produce
(A) particles that are neutral and massive
(B) a form of radiation that permeates the universe
(C) inaccurate information about the site and circumstances of the neutrino’s production
(D) charged particles and light
when a neutrino interacts with a particle in an atom of seawater, the result is a cascade of electrically charged particles and a flash of light

(E) a situation in which light and other forms of electromagnetic radiation are blocked
[Reveal] Spoiler:
D

9. According to the passage, one of the methods used to establish the properties of neutrinos was
(A) detection of photons
(B) observation of the interaction of neutrinos with gamma rays
(C) observation of neutrinos that were artificially created
since then virtually all research with neutrinos has been with neutrinos created artificially

(D) measurement of neutrinos that interacted with particles of seawater
[Reveal] Spoiler:
C
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06 Oct 2014, 03:22
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07 Dec 2016, 13:22
All correct in 12mins 21secs :D
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18 Apr 2017, 09:02
11 min 8 seconds

1 incorrect .

Last one got wrong- but knew the answer from : "since then virtually all research with neutrinos has been with neutrinos created artificially in large particle accelerators "
D mentions process for detection not helpful for studying properties. according to passage.

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Re: Virtually everything astronomers known about objects outside   [#permalink] 18 Apr 2017, 09:02
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