Reading comp PrepTest 143 · Section 2 · Question 26
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: B
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Science
Answer choices
-
AMost people believe that Remaining source text redacted.
Why choice A is not credited
Incorrect. This answer can be tempting! After all, the persistent belief seems to be about an inherent characteristic of the material. However, there's no indication in the passage that people who believe this myth also believe that it can't be fixed during the manufacturing process. It could be that they believe there could be a fix for it that just hasn't been implemented yet (or wasn't during the medieval era). -
BMost people believe that Remaining source text redacted.
Why choice B matches the stem
Correct. Question Type:
Parallel Reasoning
Strategy Overview:
Review the persistent belief, then abstract from it to create a generalization that can be used to analyze the answer choices
Answer Anticipation/Relevant Lines:
The persistent belief is stated right up front—Lines 2-4. There, it's noted that many people throughout the world believe that window glass flows downward like a liquid. This is further fleshed out in Lines 20-23, where it's applied specifically to the window panes in medieval cathedrals, where the bottoms are thicker than the tops.
So, in short, there's a persistent belief that a characteristic of a material used to make an item can explain a phenomenon with that item. Let's find an answer lining up with that.
Answer Explanation:
(Lines 2-4; Lines 6-7; Lines 20-23; Lines 44-46) Interesting answer! The persistent belief does speak to glass during the medieval era, which is analogous to early pottery. And the belief does think that flaws in those windows were due to the use of glass as opposed to some other material. This answer even brings in the Author's alternative explanation—that the error is really because of manufacturing methods of glass. Since all elements of this answer have an analogous one in the passage, and the two fit together logically, this is the correct answer.
Key Takeaway:
Note answer (C). It's analogous to another argument in the passage. This is common for Parallel Reasoning questions for passages with multiple viewpoints. Be sure to think about whether an answer aligns with a separate viewpoint, as it can be a quick way to eliminate it. -
CMost people believe that Remaining source text redacted.
Why choice C is not credited
Incorrect. (Lines 20-23) People have this belief about glass in medieval cathedrals—that's lasted quite some time, so it doesn't sound as if they have a belief about shortened life spans! -
DMost people believe that Remaining source text redacted.
Why choice D is not credited
Incorrect. (Lines 44-46) This answer is about the manufacturing process. It was the Author who believed that was the probable explanation for the phenomenon, while the persistent belief thought it was due to the materials used. -
EMost people believe that Remaining source text redacted.
Why choice E is not credited
Incorrect. (Line 7; Lines 20-23) The persistent belief is applied to both medieval cathedrals and old houses, which spand a few centuries, and there's no discussion of that belief's view towards modern houses. So this answer comparing old buildings to modern ones isn't analogous.
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Started by Ryan-Mahabir