Reading comp PrepTest 143 · Section 2 · Question 23
Passage
Questions 21-27 . To glass researchers it seems somewhat strange . that many people throughout the world share the
Remaining source text redacted.
Passage walkthrough
Passage SummaryTopic: Science
Paragraph 1
Zanotto has shown that the persistent belief that glass flows like water and this explains the thicker bottoms of medieval glass is wrong, as it would take longer than the universe has existed for that to happen, and it's probably the result of manufacturing methods.
Key Lines:
Lines 1-5 - A common belief and the fact that scientists think it's weird are introduced
Lines 8-10 - A partial reason for it is stated
Lines 20-21 - A phenomenon is noted, and the Author says that she believes an explanation related to the common belief has been debunked
Lines 44-46 - An alternative explanation is presented
Meta-Structure:
Common Belief/New Belief - This passage introduces a persistent belief shared by many (Line 3) before showing it's wrong. This metastructure is very common on the LSAT, and especially so in science passages.
Phenomenon/Explanation - Here, the Author presents a phenomenon—medieval glass is thicker at the bottom (Lines 20-23). After ruling out one explanation (Lines 20-23), she presents another (Lines 44-46).
Last Thoughts:
Remember - You don't need to know science! We don't care if you know what an amorphous atomic structure is, or if you know the atomic weight of geranium is (it doesn't have one, it's a flower! It's germanium, but it still doesn't matter). What we do want is you to tag these phrases so you can find them in case it asks about them in context.
Second, the main point. This passage has a lot going on, and we want to make sure that our anticipation of the main point is comprehensive. As such, we need to make sure that it includes the phenomenon being explained, the incorrect explanation (in some way), and the explanation put forward by the Author, along with how certain she is about each element (mainly the debunking and the new explanation).
Finally, this passage brings up a really important thing to note—and it's especially common in science passages. That's the certainty of the verb that the Author uses to describe proof (in this case, studies). There's a world of difference between a study that argues a common belief is wrong, one that provides evidence it's wrong, and one that proves it's wrong. If the Author says "argues," then we don't know her opinion on it. If she says "provides evidence," then she thinks there's a good case, but she's not sold. And if she says the study "proves" the belief is wrong, then the Author is on board. "Debunks" here is in the third camp—you can't use that verb if you don't think that the study has disproved the belief with certainty. Start to analyze these words when the Author introduces evidence!
Paragraph 1
- Paragraph note
- A myth is presented, what partly led to it is proposed, and background info on glass
- Views, minor Meta-Structures, and the author's attitude
- Myth (weird to glass experts) - Glass flows down like a liquid
- Origin - Unknown, but probably in part because of mistake on atomic structure
- Science/Structure - Liquid and glass similar, but cooling it makes it an amorphous solid
- Paragraph note
- A related phenomenon is introduced, and an explanation is debunked in a study
- Views, minor Meta-Structures, and the author's attitude
- Phenomenon - Medieval cathedrals have glass thicker at the bottom
- Explanation - Glass flows down
- Author - Zanotto study debunks this
- Zanotto - Gravity can cause solids to flow, but it'd take longer than the universe
- Paragraph note
- Zanotto's conclusions are explained
- Views, minor Meta-Structures, and the author's attitude
- GO glass - flows best - would take trillions of years
- Impurities would lessen that, but not by that much
- Flow requires 350+C (temp)
- Author - Study shows what scientists had known
- Paragraph note
- A true explanation for the earlier phenomenon is noted
- Views, minor Meta-Structures, and the author's attitude
- Explanation for thicker bottoms of medieval cathedral glass - Manufacturing processes
- Early (until 19th C) - Glass blown, which thickened some edges, and those were placed down for stability
- Later - Pulled from rod, making it more uniform
- Now - Molten tin floating, making it extremely flat
Zanotto has shown that the persistent belief that glass flows like water and this explains the thicker bottoms of medieval glass is wrong, as it would take longer than the universe has existed for that to happen, and it's probably the result of manufacturing methods.
Key Lines:
Lines 1-5 - A common belief and the fact that scientists think it's weird are introduced
Lines 8-10 - A partial reason for it is stated
Lines 20-21 - A phenomenon is noted, and the Author says that she believes an explanation related to the common belief has been debunked
Lines 44-46 - An alternative explanation is presented
Meta-Structure:
Common Belief/New Belief - This passage introduces a persistent belief shared by many (Line 3) before showing it's wrong. This metastructure is very common on the LSAT, and especially so in science passages.
Phenomenon/Explanation - Here, the Author presents a phenomenon—medieval glass is thicker at the bottom (Lines 20-23). After ruling out one explanation (Lines 20-23), she presents another (Lines 44-46).
Last Thoughts:
Remember - You don't need to know science! We don't care if you know what an amorphous atomic structure is, or if you know the atomic weight of geranium is (it doesn't have one, it's a flower! It's germanium, but it still doesn't matter). What we do want is you to tag these phrases so you can find them in case it asks about them in context.
Second, the main point. This passage has a lot going on, and we want to make sure that our anticipation of the main point is comprehensive. As such, we need to make sure that it includes the phenomenon being explained, the incorrect explanation (in some way), and the explanation put forward by the Author, along with how certain she is about each element (mainly the debunking and the new explanation).
Finally, this passage brings up a really important thing to note—and it's especially common in science passages. That's the certainty of the verb that the Author uses to describe proof (in this case, studies). There's a world of difference between a study that argues a common belief is wrong, one that provides evidence it's wrong, and one that proves it's wrong. If the Author says "argues," then we don't know her opinion on it. If she says "provides evidence," then she thinks there's a good case, but she's not sold. And if she says the study "proves" the belief is wrong, then the Author is on board. "Debunks" here is in the third camp—you can't use that verb if you don't think that the study has disproved the belief with certainty. Start to analyze these words when the Author introduces evidence!
Question prompt
Which one of the
Remaining source text redacted.
Why the credited answer is right
Credited answer: A
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Science
Answer choices
-
AThey provide some important Remaining source text redacted.
Why choice A matches the stem
Correct. Question Type:
Author's Attitude
Strategy Overview:
Use our notes to find where Zanotto's study is discussed and check anything we tagged as showing the Author's attitude
Answer Anticipation/Relevant Lines:
Taking a look at our notes, we can see that Paragraphs 2 and 3 are the ones that discuss Zanotto's study, and we highlighted two parts of the Author's opinion.
First, in Lines 20-23, the Author said that the new study "debunks" the belief that medieval glass flowed down over time, explaining the thicker bases. That verb conveys that the Author is 100% on board with the study proving that explanation wrong.
Second, in Lines 39-43, the Author said that the study "demonstrates dramatically" something scientists had known—that glass down flow to any meaningful degree.
Both statements reflect largely the same idea—that the Zanotto study effectively disproved the glass-flow explanation for the medieval glass thickness, and the latter also suggests that scientists already thought this was true. Let's find an answer reflecting that view.
Answer Explanation:
(Line 1; Lines 20-23; Lines 39-43) The Author states that Zanotto's study "debunks" a common belief, "demonstrat[ing] dramatically" that it's wrong. This view "seem[ed] somewhat strange" to glass experts, and scientists "had reasoned earlier" this was the case. And Zanotto's study had "calculations" as to the number of years it would take glass to flow. As such, the Author does believe Zanotto provided quantitative data (calculations/years) that supports the view scientists already held (glass doesn't flow to a meaningful degree). This answer is correct. Note that it doesn't directly convey the idea that the study debunked a belief, but it does indirectly do so by saying it supports the view of scientists, and those scientists believed the myth was wrong.
Key Takeaway:
Understand the viewpoints in a passage, and be sure to keep them straight! Analyzing these answers required understanding the difference between the common myth, what scientists thought, Zanotto's study, and the Author's view. The latter three were largely aligned against the first, but there were still some differences between the scope of their beliefs that were important to note. -
BThey have stimulated important Remaining source text redacted.
Why choice B is not credited
Incorrect. (Liens 39-40; Lines 1-2) Zanotto's study "demonstrates dramatically" what scientists had already reasoned. As such, it didn't stimulate new research into something scientists had thought settled—it provided dramatic affirmation of that topic. -
CThey offer a highly Remaining source text redacted.
Why choice C is not credited
Incorrect. (Lines 8-10) This can be a tricky answer because of how it's phrased. However, for this answer to be correct, the Author would have to believe that Zanotto's study spoke to why the idea became popularly believed. However, Zanotto's study doesn't address that. The closest we get to addressing this issue is the partial potential answer presented by the Author in Paragraph 1. -
DThey provide a conceptual Remaining source text redacted.
Why choice D is not credited
Incorrect. (Liens 20-22; Lines 39-40) The study shows that the common belief is wrong and the scientists are right. First, this answer is wrong in talking about two scientific views, when there was only one. Second, it talks about reconciling views when it instead shows one to be right and one to be wrong. Third, the views are incompatible—either glass flow is a factor in medieval glass panes, or it isn't. -
EThey suggest that neither Remaining source text redacted.
Why choice E is not credited
Incorrect. (Line 20-23) Zanotto's study did debunk one explanation for the thicker bottoms to medieval glass panes. However, the second hypothesis is stated in Paragraph 4, and Zanotto's study doesn't debunk that one. In fact, it's presented by the Author, who accepts the results of Zanotto's study—it'd be weird for her to put forward an explanation that was debunked by a study she accepts!
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