Events & Promotions
|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Nov 2211:00 AM IST
-01:00 PM IST
Do RC/MSR passages scare you? e-GMAT is conducting a masterclass to help you learn – Learn effective reading strategies Tackle difficult RC & MSR with confidence Excel in timed test environment- Nov 23
11:00 AM IST
-01:00 PM IST
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease. 
Nov 2510:00 AM EST
-11:00 AM EST
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors.
20 Dec 2022, 10:29
Kudos
Bookmarks
Official Explanation
The discovery of which of the following would call into question the conclusion mentioned in line 16 [The evident conclusion—that asteroids larger than 200 meters across are multicomponent structures or rubble piles—agrees with recent computer modeling of collisions, which also finds a transition at that diameter.]?
Difficulty Level: 700
Explanation
Application
The conclusion that the text in line 16 points to is that asteroids with diameters greater than 200 meters are multicomponent structures or rubble piles. To call that conclusion into question, an observation would have to suggest that asteroids larger than 200 meters across are not such multicomponent structures. According to the first paragraph, rubble piles cannot be fast rotators: spinning faster than once every few hours would make them fly apart.
A. Nothing in the passage suggests that the behavior of an asteroid 100 meters in diameter is relevant to a conclusion about the behavior of asteroids greater than 200 meters in diameter.
B. Nothing in the passage suggests that the behavior of an asteroid 150 meters in diameter would have any effect on a conclusion about the constitution of asteroids with diameters greater than 200 meters.
C. An asteroid 250 meters in diameter rotating at a rate of once per week would be rotating at a slow enough rate to hold together a pile of rubble. Thus, this observation would be entirely consistent with the conclusion about asteroids larger than 200 meters in diameter.
D. Correct. Assuming that an asteroid composed of a pile of rubble is of a great enough density, a rotation rate greater than one revolution every few hours would make it fly apart. So a 500-meter asteroid rotating at a rate of once per hour—that is, faster than the crucial speed—would fly apart if it were not a monolith. The conclusion states that all asteroids larger than 200 meters are multicomponent structures (that is, are not monoliths), so the discovery of a 500-meter asteroid rotating at a rate of once an hour would call into question that conclusion.
E. An asteroid rotating at a rate of once every 24 hours would, regardless of size, be rotating much more slowly than the once every few hours that the passage claims would make a pile of rubble of a sufficient density fly apart. So an asteroid with a diameter of 1,000 meters that rotated once per day could be a pile of rubble and not conflict with the conclusion.
The correct answer is D.
Difficulty Level: 700
Explanation
Application
The conclusion that the text in line 16 points to is that asteroids with diameters greater than 200 meters are multicomponent structures or rubble piles. To call that conclusion into question, an observation would have to suggest that asteroids larger than 200 meters across are not such multicomponent structures. According to the first paragraph, rubble piles cannot be fast rotators: spinning faster than once every few hours would make them fly apart.
A. Nothing in the passage suggests that the behavior of an asteroid 100 meters in diameter is relevant to a conclusion about the behavior of asteroids greater than 200 meters in diameter.
B. Nothing in the passage suggests that the behavior of an asteroid 150 meters in diameter would have any effect on a conclusion about the constitution of asteroids with diameters greater than 200 meters.
C. An asteroid 250 meters in diameter rotating at a rate of once per week would be rotating at a slow enough rate to hold together a pile of rubble. Thus, this observation would be entirely consistent with the conclusion about asteroids larger than 200 meters in diameter.
D. Correct. Assuming that an asteroid composed of a pile of rubble is of a great enough density, a rotation rate greater than one revolution every few hours would make it fly apart. So a 500-meter asteroid rotating at a rate of once per hour—that is, faster than the crucial speed—would fly apart if it were not a monolith. The conclusion states that all asteroids larger than 200 meters are multicomponent structures (that is, are not monoliths), so the discovery of a 500-meter asteroid rotating at a rate of once an hour would call into question that conclusion.
E. An asteroid rotating at a rate of once every 24 hours would, regardless of size, be rotating much more slowly than the once every few hours that the passage claims would make a pile of rubble of a sufficient density fly apart. So an asteroid with a diameter of 1,000 meters that rotated once per day could be a pile of rubble and not conflict with the conclusion.
The correct answer is D.
20 Dec 2022, 10:32
Kudos
Bookmarks
Official Explanation
According to the passage, which of the following is a prediction that is based on the strength of the gravitational attraction of small asteroids?
Difficulty Level: 600-650
Explanation
Supporting Idea
Regarding small asteroids, the second paragraph states that they have feeble gravity. Any fragments from impacts would escape that gravity, and thus, the passage states, the small asteroids should be monolithic.
A. Small asteroids could be few in number, but the passage does not offer such a prediction.
B. Correct. This prediction is offered in the second paragraph, based on the fact that small asteroids do not have strong gravitational attraction. Any impact fragments will easily escape the weak gravitational attraction of the small asteroids.
C. The passage discusses large asteroids collisions in more detail than small-asteroid collisions, but it provides no basis for predicting how often large and small asteroids will, comparatively, be involved in such collisions.
D. The first paragraph indicates that the rotation rates of small asteroids can exceed the upper limit on the rotation rates of large asteroids, but it does not indicate that most small asteroids have rotation rates that exceed this upper limit.
E. The passage only indicates that there are few observed exceptions to the upper limit on rotation rates of large asteroids, and these exceptions are all smaller than 200 meters in diameter; the passage does not indicate that there are few small asteroids that have very slow rotation rates.
The correct answer is B.
Difficulty Level: 600-650
Explanation
Supporting Idea
Regarding small asteroids, the second paragraph states that they have feeble gravity. Any fragments from impacts would escape that gravity, and thus, the passage states, the small asteroids should be monolithic.
A. Small asteroids could be few in number, but the passage does not offer such a prediction.
B. Correct. This prediction is offered in the second paragraph, based on the fact that small asteroids do not have strong gravitational attraction. Any impact fragments will easily escape the weak gravitational attraction of the small asteroids.
C. The passage discusses large asteroids collisions in more detail than small-asteroid collisions, but it provides no basis for predicting how often large and small asteroids will, comparatively, be involved in such collisions.
D. The first paragraph indicates that the rotation rates of small asteroids can exceed the upper limit on the rotation rates of large asteroids, but it does not indicate that most small asteroids have rotation rates that exceed this upper limit.
E. The passage only indicates that there are few observed exceptions to the upper limit on rotation rates of large asteroids, and these exceptions are all smaller than 200 meters in diameter; the passage does not indicate that there are few small asteroids that have very slow rotation rates.
The correct answer is B.
20 Dec 2022, 10:35
Kudos
Bookmarks
Official Explanation
The author of the passage mentions “escape velocity” (see line 22) in order to help explain which of the following?
Difficulty Level: 750
Explanation
Evaluation
This question asks about the purpose of the author’s use of the phrase escape velocity in the second paragraph. The author is discussing what occurs after an asteroid collision, in which a large asteroid might be blasted to bits. The bits, according to the author, will move slower than their mutual escape velocity—that is, the speed at which they would have to move to get away from each other and not reassemble, under the influence of gravity, into a rubble pile.
A. The author is emphasizing the asteroid bits that do not escape rather than those that do. Asteroids may become smaller over time, but the fact that most bits move slower than their escape velocity would not help to explain this shrinkage.
B. That the bits of asteroid move slower than their escape velocity helps explain why the fragments reassemble, but it does not help explain the speed with which they reassemble.
C. According to the author, asteroid collisions occur frequently, but the escape velocity of the resulting fragments does not help to explain that frequency.
D. The concept of escape velocity may help explain why small asteroids are monoliths, but it has no relevance, at least as far as the passage indicates, to those asteroids’ rotation rates.
E. Correct. After a collision, it is the asteroid fragments’ failure to reach escape velocity that allows the fragments’ gravitational pull to reassemble them into a rubble pile.
The correct answer is E.
Difficulty Level: 750
Explanation
Evaluation
This question asks about the purpose of the author’s use of the phrase escape velocity in the second paragraph. The author is discussing what occurs after an asteroid collision, in which a large asteroid might be blasted to bits. The bits, according to the author, will move slower than their mutual escape velocity—that is, the speed at which they would have to move to get away from each other and not reassemble, under the influence of gravity, into a rubble pile.
A. The author is emphasizing the asteroid bits that do not escape rather than those that do. Asteroids may become smaller over time, but the fact that most bits move slower than their escape velocity would not help to explain this shrinkage.
B. That the bits of asteroid move slower than their escape velocity helps explain why the fragments reassemble, but it does not help explain the speed with which they reassemble.
C. According to the author, asteroid collisions occur frequently, but the escape velocity of the resulting fragments does not help to explain that frequency.
D. The concept of escape velocity may help explain why small asteroids are monoliths, but it has no relevance, at least as far as the passage indicates, to those asteroids’ rotation rates.
E. Correct. After a collision, it is the asteroid fragments’ failure to reach escape velocity that allows the fragments’ gravitational pull to reassemble them into a rubble pile.
The correct answer is E.
