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Updated on: 08 Jun 2021, 01:59
Originally posted by srij13 on 23 Sep 2019, 12:15.
Last edited by Sajjad1994 on 08 Jun 2021, 01:59, edited 3 times in total.
Last edited by Sajjad1994 on 08 Jun 2021, 01:59, edited 3 times in total.
Added Qs 4-7
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Question 1
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
25%
(medium)
Question Stats:
73% (02:56) correct
27%
(02:45) wrong
based on 376
sessions
History
Date
Time
Result
Not Attempted Yet
Question 2
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
25%
(medium)
Question Stats:
72% (01:14) correct 28%
(01:25) wrong
based on 367
sessions
History
Date
Time
Result
Not Attempted Yet
Question 3
D
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
25%
(medium)
Question Stats:
68% (01:02) correct 32%
(01:21) wrong
based on 351
sessions
History
Date
Time
Result
Not Attempted Yet
Question 4
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
45%
(medium)
Question Stats:
56% (00:58) correct 44%
(01:07) wrong
based on 151
sessions
History
Date
Time
Result
Not Attempted Yet
Question 5
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
45%
(medium)
Question Stats:
55% (01:05) correct 45%
(01:10) wrong
based on 146
sessions
History
Date
Time
Result
Not Attempted Yet
Question 6
D
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
49% (01:12) correct 51%
(01:12) wrong
based on 135
sessions
History
Date
Time
Result
Not Attempted Yet
Question 7
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
35%
(medium)
Question Stats:
63% (01:09) correct 37%
(01:14) wrong
based on 136
sessions
History
Date
Time
Result
Not Attempted Yet
New Project RC Butler 2019 - Practice 2 RC Passages Everyday
Passage # 350, Date : 24-Sep-2019
This post is a part of New Project RC Butler 2019. Click here for Details
Passage # 350, Date : 24-Sep-2019
This post is a part of New Project RC Butler 2019. Click here for Details
Before plans can be finalized for a space station that maintains a low-earth orbit, scientists must first answer questions about the durability of materials involved in its construction, allowing them to determine which sections of the space station will need the greatest protection and to ensure that such a craft is not overprotected and consequently too heavy. In 1984 NASA deployed a satellite called the Long-Duration Exposure Facility (LDEF). Each of LDEF’s experimental specimens—materials intended for use in the construction of spacecraft—was mounted on the LDEF surface. LDEF was balanced to maintain a constant near-vertical orientation, leaning slightly forward, so that the satellite did not spin while it orbited the earth. This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation.
Initial reports indicate that LDEF could yield much invaluable information. LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces. Atomic oxygen, comprising most of the low-earth orbit atmosphere, is much less stable than molecular oxygen. It has no thermal velocity, and as a result, it is effectively motionless. Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels (eventually abandoning them in its wake) and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen. The data promise to yield other useful insights.
Initial reports indicate that LDEF could yield much invaluable information. LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces. Atomic oxygen, comprising most of the low-earth orbit atmosphere, is much less stable than molecular oxygen. It has no thermal velocity, and as a result, it is effectively motionless. Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels (eventually abandoning them in its wake) and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen. The data promise to yield other useful insights.
The phrase can be inferred in the question stem indicates that this is an inference question. The task of the question is indicated by the words inferred and EXCEPT. In order to answer the question, identify which answer choice cannot be supported by the information in the passage. The subject of the question is the passage as a whole.
Choice A: No. The second paragraph states that LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces. Therefore, this statement can be inferred from the passage.
Choice B: No. The last sentence of the first paragraph states This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation. In the second paragraph the passage states LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces…Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels (eventually abandoning them in its wake) and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen. Therefore, this answer choice can be inferred from the passage.
Choice C: Correct. This choice contains the extreme wording most and cannot and is not supported by the text which does not reference the length of tenure in space of most communications satellites.
Choice D: No. The first sentence of the passage indicates that scientists must first answer questions about the durability of materials involved in its construction, allowing them to determine which sections of the space station will need the greatest protection and to ensure that such a craft is not overprotected and consequently too heavy. Therefore, it can be inferred from the passage that weight does constitute a major design consideration.
Choice E: No. The fourth sentence of the second paragraph indicates that (atomic oxygen) has no thermal velocity, and as a result, it is effectively motionless, which matches the information in this answer choice.
The correct answer is choice C.
Choice A: No. The second paragraph states that LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces. Therefore, this statement can be inferred from the passage.
Choice B: No. The last sentence of the first paragraph states This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation. In the second paragraph the passage states LDEF data have already revealed the damage atomic oxygen causes and confirmed that its effects are much more pronounced on leading than on trailing surfaces…Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels (eventually abandoning them in its wake) and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen. Therefore, this answer choice can be inferred from the passage.
Choice C: Correct. This choice contains the extreme wording most and cannot and is not supported by the text which does not reference the length of tenure in space of most communications satellites.
Choice D: No. The first sentence of the passage indicates that scientists must first answer questions about the durability of materials involved in its construction, allowing them to determine which sections of the space station will need the greatest protection and to ensure that such a craft is not overprotected and consequently too heavy. Therefore, it can be inferred from the passage that weight does constitute a major design consideration.
Choice E: No. The fourth sentence of the second paragraph indicates that (atomic oxygen) has no thermal velocity, and as a result, it is effectively motionless, which matches the information in this answer choice.
The correct answer is choice C.
A. Chemical compounds that constitute hazards to a spacecraft already exist in the orbital atmosphere.
B. Some of the experiments carried by LDEF have already yielded useful results.
C. Most communications satellites cannot endure a long tenure in space.
D. Weight constitutes a major design consideration for those planning the construction of a spacecraft.
E. Elements with no thermal velocity can be considered, for all practical purposes, motionless.
The phrase according to the passage indicates that this is a retrieval question. The subject of the question is care taken in the design of the LDEF spacecraft. The task of the question is to determine what the passage states about the subject and evaluate the answer choices, eliminating any choice which cannot be supported by the text. According to the first paragraph of the passage, Each of LDEF’s experimental specimens—materials intended for use in the construction of spacecraft—was mounted on the LDEF surface. LDEF was balanced to maintain a constant near-vertical orientation, leaning slightly forward, so that the satellite did not spin while it orbited the earth. This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation.
Choice A: No. There is no such comparison in the passage of the number of chemical reactions between the materials in its experiment trays and those elements naturally occurring in space.
Choice B: Correct. This choice is supported by the text in the first paragraph which states LDEF was balanced to maintain a constant near-vertical orientation…so that the satellite did not spin while it orbited the earth…(and) allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation. This matches the information in the answer choice indicating that LDEF was designed to maintain a constant position relative to its orbit, enabling scientists to measure the results of a variety of impacts.
Choice C: No. This answer choice contains the extreme language any and even in the unlikely event that debris was many times its weight. Although the passage mentions that scientists understand to what degree an object’s orientation affects the damage caused by atomic oxygen, it does not indicate that LDEF would survive the impact of any space debris.
Choice D: No. This choice contains the recycled language atomic oxygen as well as the extreme language entirely avoiding others. Although the passage states, Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels…and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen, there is no such comparison of the impacts, or lack thereof, of space hazards.
Choice E: No. This choice contains the recycled language orientation, "leading" and "trailing”. Although the passage states that LDEF was balanced to maintain a constant near-vertical orientation…so that the satellite did not spin while it orbited the earth, there is no indication that scientists adjusted the orientation of its "leading" and "trailing" surfaces. The passage indicates that LDEF was balanced in this manner to allow scientists to measure damage caused to “leading” and “trailing” parts.
The correct answer is choice B.
Choice A: No. There is no such comparison in the passage of the number of chemical reactions between the materials in its experiment trays and those elements naturally occurring in space.
Choice B: Correct. This choice is supported by the text in the first paragraph which states LDEF was balanced to maintain a constant near-vertical orientation…so that the satellite did not spin while it orbited the earth…(and) allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation. This matches the information in the answer choice indicating that LDEF was designed to maintain a constant position relative to its orbit, enabling scientists to measure the results of a variety of impacts.
Choice C: No. This answer choice contains the extreme language any and even in the unlikely event that debris was many times its weight. Although the passage mentions that scientists understand to what degree an object’s orientation affects the damage caused by atomic oxygen, it does not indicate that LDEF would survive the impact of any space debris.
Choice D: No. This choice contains the recycled language atomic oxygen as well as the extreme language entirely avoiding others. Although the passage states, Scientists now know that a fast-moving object in space sweeps up oxygen atoms as it travels…and they understand to what degree an object’s orientation affects the damage caused by atomic oxygen, there is no such comparison of the impacts, or lack thereof, of space hazards.
Choice E: No. This choice contains the recycled language orientation, "leading" and "trailing”. Although the passage states that LDEF was balanced to maintain a constant near-vertical orientation…so that the satellite did not spin while it orbited the earth, there is no indication that scientists adjusted the orientation of its "leading" and "trailing" surfaces. The passage indicates that LDEF was balanced in this manner to allow scientists to measure damage caused to “leading” and “trailing” parts.
The correct answer is choice B.
A. would maximize the number of chemical reactions between the materials in its experiment trays and those elements naturally occurring in space
B. would maintain a constant position relative to its orbit, enabling scientists to measure the results of a variety of impacts
C. would survive the impact of any space debris, even in the unlikely event that debris was many times its weight
D. could position itself so as to maximize impact with some space hazards, such as atomic oxygen, while entirely avoiding others
E. could maneuver itself into a more advantageous position by adjusting the orientation of its "leading" and "trailing" surfaces
This is a primary purpose question, as indicated by the phrase main idea of the passage. The task of the question is to determine why the author wrote the passage, which means that the subject of the question is the passage as a whole. To answer the question, determine why the author wrote the passage, then evaluate the answer choices, eliminating any choice which does not match the author’s primary purpose. The first paragraph describes a satellite called the Long-Duration Exposure Facility (LDEF), which was used to determine the durability of materials to be used in the construction of a space station that maintains a low-earth orbit. The second paragraph describes some of the invaluable information LDEF could yield. The passage concludes by asserting (LDEF) data promise to yield other useful insights. Therefore, the main idea of the passage is to describe the LDEF and insights it has provided that will assist with the eventual construction of a space station.
Choice A: No. This choice contains the extreme language cannot and most and there is no such comparison of the number of experiments that have yielded results. Additionally, this choice could be considered a reversal since LDEF has already been presented as a potential success because the passage states that initial reports indicate that LDEF could yield much invaluable information.
Choice B: No. The word key is extreme language and this choice is a memory trap. Although the passage mentions that scientists were able to measure damage caused to “leading” and “trailing” parts of a spacecraft, there is no such comparison of the preparatory tasks involved in designing a successful space station.
Choice C: No. The phrase will lead to unexpected advances in space travel is extreme language. Although the passage states in the last sentence that the data promise to yield other useful insights, it is not definite.
Choice D: Correct. This choice accurately paraphrases the main idea of the passage by combining information from both the first and last sentence of the passage. The results of LDEF experiments may provide previously unavailable information matches the final sentence – The data promise to yield other useful insights. While the second part of the answer choice that states is necessary to design a space station sturdy enough to endure a long term in orbit, matches the questions scientists must first answer about the durability of materials before plans can be finalized for a space station that maintains a low-earth orbit.
Choice E: No. This choice contains the extreme language one of space's busiest traffic zones. Although the passage mentions the construction of a space station that maintains a low-earth orbit, there is no such comparison of the activity levels of space zones.
The correct answer is choice D.
Choice A: No. This choice contains the extreme language cannot and most and there is no such comparison of the number of experiments that have yielded results. Additionally, this choice could be considered a reversal since LDEF has already been presented as a potential success because the passage states that initial reports indicate that LDEF could yield much invaluable information.
Choice B: No. The word key is extreme language and this choice is a memory trap. Although the passage mentions that scientists were able to measure damage caused to “leading” and “trailing” parts of a spacecraft, there is no such comparison of the preparatory tasks involved in designing a successful space station.
Choice C: No. The phrase will lead to unexpected advances in space travel is extreme language. Although the passage states in the last sentence that the data promise to yield other useful insights, it is not definite.
Choice D: Correct. This choice accurately paraphrases the main idea of the passage by combining information from both the first and last sentence of the passage. The results of LDEF experiments may provide previously unavailable information matches the final sentence – The data promise to yield other useful insights. While the second part of the answer choice that states is necessary to design a space station sturdy enough to endure a long term in orbit, matches the questions scientists must first answer about the durability of materials before plans can be finalized for a space station that maintains a low-earth orbit.
Choice E: No. This choice contains the extreme language one of space's busiest traffic zones. Although the passage mentions the construction of a space station that maintains a low-earth orbit, there is no such comparison of the activity levels of space zones.
The correct answer is choice D.
A. It cannot be determined whether LDEF was a success, since most of its experiments have not yet yielded results.
B. Determining the different types of damage done to leading and trailing components of a spacecraft is the key preparatory task involved in designing a successful space station.
C. The development of new technologies resulting from the LDEF project will lead to unexpected advances in space travel.
D. The results of LDEF experiments may provide previously unavailable information that is necessary to design a space station sturdy enough to endure a long term in orbit.
E. It is necessary to construct a space station in order to monitor the atmospheric conditions in one of space's busiest traffic zones.
4. Which of the following is characteristic of much of the oxygen found in low-earth orbit?
A. It is indistinguishable from typical, atmospheric oxygen.
B. It is more reactive than is molecular oxygen.
C. |t poses a significant threat to the stability of the planned space station.
D. It moves at a much higher velocity than does molecular oxygen.
E. It was first discovered by scientists working on the LDEF project.
A. It is indistinguishable from typical, atmospheric oxygen.
B. It is more reactive than is molecular oxygen.
C. |t poses a significant threat to the stability of the planned space station.
D. It moves at a much higher velocity than does molecular oxygen.
E. It was first discovered by scientists working on the LDEF project.
5. It can be inferred from the passage that the rotation of an object orbiting the earth
A. can be neutralized in the design process
B. will cause the object to maintain a near vertical orientation
C. is determined by the weight of the object itself
D. is caused by a combination of space-borne elements and atmospheric pressure
E. cannot be maintained indefinitely without the imposition of an outside force such as atmospheric oxygen
A. can be neutralized in the design process
B. will cause the object to maintain a near vertical orientation
C. is determined by the weight of the object itself
D. is caused by a combination of space-borne elements and atmospheric pressure
E. cannot be maintained indefinitely without the imposition of an outside force such as atmospheric oxygen
6. It can be inferred from the passage that which of the following is true of the construction of a low-earth orbit space station?
A. A space station must be able to withstand collisions from molecular oxygen if it is to be viable.
B. Scientists must devise a way to stabilize atomic oxygen before they can design a low-earth orbit space station.
C. Design engineers will have to underprotect certain less vulnerable portions of the Spacecraft in order to contain the costs of such a large project.
D. A the station's weight is one of the concerns of the scientists working on the craft.
E. Were scientists to discover that atomic oxygen had thermal velocity, all data collected by LDEF would be rendered useless.
A. A space station must be able to withstand collisions from molecular oxygen if it is to be viable.
B. Scientists must devise a way to stabilize atomic oxygen before they can design a low-earth orbit space station.
C. Design engineers will have to underprotect certain less vulnerable portions of the Spacecraft in order to contain the costs of such a large project.
D. A the station's weight is one of the concerns of the scientists working on the craft.
E. Were scientists to discover that atomic oxygen had thermal velocity, all data collected by LDEF would be rendered useless.
7. The author implies that, were the LDEF to rotate during its orbit of the earth,
A. the data its experiments yielded would not have been pertinent to questions concerning the directional nature of damage to the spacecraft
B. the data from experimental materials mounted within LDEF would have been accurate, but data from the measuring devices mounted on its outside would have been tainted
C. the craft would not have swept up atomic oxygen as it traveled through its orbit
D. the craft would have been damaged by massive exposure to Space-borne radiation
E. scientists would not have been able to determine the thermal velocity of atomic oxygen
A. the data its experiments yielded would not have been pertinent to questions concerning the directional nature of damage to the spacecraft
B. the data from experimental materials mounted within LDEF would have been accurate, but data from the measuring devices mounted on its outside would have been tainted
C. the craft would not have swept up atomic oxygen as it traveled through its orbit
D. the craft would have been damaged by massive exposure to Space-borne radiation
E. scientists would not have been able to determine the thermal velocity of atomic oxygen
25 Sep 2019, 01:22
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Q.1
A - Refers to Atomic Oxygen
B - Second Para is a basic mention of the same
C - Communication satellites not mentioned
D - Mentioned in the 1st para, we have to consider not to add too much material, for weight considerations
E - Mentioned Verbatim in 2nd Para
Q.2
"LDEF was balanced to maintain a constant near-vertical orientation, leaning slightly forward, so that the satellite did not spin while it orbited the earth. This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation."
Hence B
Q.3
2 Major Points
- We need to check the materials possible before designing a space station
- The LDEF collected pertinent information regarding the same
Hence Option D
A - Refers to Atomic Oxygen
B - Second Para is a basic mention of the same
C - Communication satellites not mentioned
D - Mentioned in the 1st para, we have to consider not to add too much material, for weight considerations
E - Mentioned Verbatim in 2nd Para
Q.2
"LDEF was balanced to maintain a constant near-vertical orientation, leaning slightly forward, so that the satellite did not spin while it orbited the earth. This feature allowed scientists to measure damage caused to “leading” and “trailing” parts of a spacecraft and to what extent the damage suffered was affected by the craft’s orientation."
Hence B
Q.3
2 Major Points
- We need to check the materials possible before designing a space station
- The LDEF collected pertinent information regarding the same
Hence Option D
06 Dec 2019, 01:11
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Official Answer to Ques 3
This is a primary purpose question, as indicated by the phrase main idea of the passage. The task of the question is to determine why the author wrote the passage, which means that the subject of the question is the passage as a whole. To answer the question, determine why the author wrote the passage, then evaluate the answer choices, eliminating any choice which does not match the author’s primary purpose. The first paragraph describes a satellite called the Long-Duration Exposure Facility (LDEF), which was used to determine the durability of materials to be used in the construction of a space station that maintains a low-earth orbit. The second paragraph describes some of the invaluable information LDEF could yield. The passage concludes by asserting (LDEF) data promise to yield other useful insights. Therefore, the main idea of the passage is to describe the LDEF and insights it has provided that will assist with the eventual construction of a space station.
Choice A: No. This choice contains the extreme language cannot and most and there is no such comparison of the number of experiments that have yielded results. Additionally, this choice could be considered a reversal since LDEF has already been presented as a potential success because the passage states that initial reports indicate that LDEF could yield much invaluable information.
Choice B: No. The word key is extreme language and this choice is a memory trap. Although the passage mentions that scientists were able to measure damage caused to “leading” and “trailing” parts of a spacecraft, there is no such comparison of the preparatory tasks involved in designing a successful space station.
Choice C: No. The phrase will lead to unexpected advances in space travel is extreme language. Although the passage states in the last sentence that the data promise to yield other useful insights, it is not definite.
Choice D: Correct. This choice accurately paraphrases the main idea of the passage by combining information from both the first and last sentence of the passage. The results of LDEF experiments may provide previously unavailable information matches the final sentence – The data promise to yield other useful insights. While the second part of the answer choice that states is necessary to design a space station sturdy enough to endure a long term in orbit, matches the questions scientists must first answer about the durability of materials before plans can be finalized for a space station that maintains a low-earth orbit.
Choice E: No. This choice contains the extreme language one of space's busiest traffic zones. Although the passage mentions the construction of a space station that maintains a low-earth orbit, there is no such comparison of the activity levels of space zones.
The correct answer is choice D.
This is a primary purpose question, as indicated by the phrase main idea of the passage. The task of the question is to determine why the author wrote the passage, which means that the subject of the question is the passage as a whole. To answer the question, determine why the author wrote the passage, then evaluate the answer choices, eliminating any choice which does not match the author’s primary purpose. The first paragraph describes a satellite called the Long-Duration Exposure Facility (LDEF), which was used to determine the durability of materials to be used in the construction of a space station that maintains a low-earth orbit. The second paragraph describes some of the invaluable information LDEF could yield. The passage concludes by asserting (LDEF) data promise to yield other useful insights. Therefore, the main idea of the passage is to describe the LDEF and insights it has provided that will assist with the eventual construction of a space station.
Choice A: No. This choice contains the extreme language cannot and most and there is no such comparison of the number of experiments that have yielded results. Additionally, this choice could be considered a reversal since LDEF has already been presented as a potential success because the passage states that initial reports indicate that LDEF could yield much invaluable information.
Choice B: No. The word key is extreme language and this choice is a memory trap. Although the passage mentions that scientists were able to measure damage caused to “leading” and “trailing” parts of a spacecraft, there is no such comparison of the preparatory tasks involved in designing a successful space station.
Choice C: No. The phrase will lead to unexpected advances in space travel is extreme language. Although the passage states in the last sentence that the data promise to yield other useful insights, it is not definite.
Choice D: Correct. This choice accurately paraphrases the main idea of the passage by combining information from both the first and last sentence of the passage. The results of LDEF experiments may provide previously unavailable information matches the final sentence – The data promise to yield other useful insights. While the second part of the answer choice that states is necessary to design a space station sturdy enough to endure a long term in orbit, matches the questions scientists must first answer about the durability of materials before plans can be finalized for a space station that maintains a low-earth orbit.
Choice E: No. This choice contains the extreme language one of space's busiest traffic zones. Although the passage mentions the construction of a space station that maintains a low-earth orbit, there is no such comparison of the activity levels of space zones.
The correct answer is choice D.
