Newly made glass is very strong, but it begins to lose strength the instant it is made. Simply blowing on...
GMAT Reading Comprehension : (RC) Questions
Newly made glass is very strong, but it begins to lose strength the instant it is made. Simply blowing on its surface can significantly reduce its strength. And while glass has the capacity to bear heavy loads—a necessary requirement in structural applications—it cannot easily withstand bending forces. Protective coatings are one way to give glass greater strength, although this can affect transparency, one of the main reasons for using glass. Also, altering the composition of the glass can make it harder for cracks to form, but this alteration can mean loss of other desirable properties, or make the glass more expensive to manufacture.
The manufacturing process can be modified to keep the surface of the glass clear and free of cracks. Strong, clear glass for laptop displays is made by maximizing the surface area in contact only with air as the glass cools. But with glass used for structural purposes, tempering processes are typically used. In heat tempering the surface of the glass is cooled more rapidly than the interior, a process that allows the interior of the glass to become more dense. In chemical tempering the sodium ions at the surface are replaced with potassium ions, which are larger, and this achieves much the same compression as does the heat tempering process.
Tempering makes cracks less likely to form, but breakages can still occur. When tempered glass breaks, it breaks into many smaller pieces than does ordinary glass. In structural applications this is actually preferred, since smaller pieces are generally less likely to cause injury. Use of laminated glass in a structure helps to maintain the structure's integrity in the event that the glass breaks. Glass is laminated by sandwiching thin polymer layers between layers of glass. This adds strength and keeps large broken pieces from shattering. One problem with this, however, is that it makes fabricating glass for structural purposes very difficult, since each piece must be cut, polished, and drilled for the connecting fittings before it is tempered. In fabrication, precise measurements and extremely small margins of error are needed to avoid potentially destructive stresses in the assembled structure.
Which of the following terms, if substituted for the term "integrity" in the highlighted sentence, would LEAST alter the meaning of the sentence?
1. Passage Analysis:
Progressive Passage Analysis
| Text from Passage | Analysis |
|---|---|
| Newly made glass is very strong, but it begins to lose strength the instant it is made. | What it says: Fresh glass starts strong but immediately gets weaker What it does: Introduces the central paradox/problem with glass Source/Type: Factual statement about glass properties Connection to Previous Sentences: Opening sentence - establishes the foundation Visualization: Imagine glass strength starting at 100% but dropping to 95%, 90%, 85% as time passes Reading Strategy Insight: This sets up the main challenge - the rest will likely explain this problem and solutions |
| Simply blowing on its surface can significantly reduce its strength. | What it says: Even gentle air contact weakens glass dramatically What it does: Provides a specific, dramatic example of the weakness problem Source/Type: Factual example supporting the previous claim Connection to Previous Sentences: This directly supports sentence 1 by showing HOW glass loses strength - even the gentlest contact causes problems Visualization: Glass at 100% strength → gentle breath → drops to 70% strength Reading Strategy Insight: This is amplification, not new complexity - it's making the first point more concrete and dramatic |
| And while glass has the capacity to bear heavy loads—a necessary requirement in structural applications—it cannot easily withstand bending forces. | What it says: Glass can hold weight but breaks when bent What it does: Introduces a specific application context (structural use) and another limitation Source/Type: Factual statement about glass limitations in construction Connection to Previous Sentences: Builds on the weakness theme by adding a SECOND type of weakness - not just surface fragility, but also bending problems Visualization: Glass beam holds 1000 pounds straight down ✓, but bends and breaks under 50 pounds of sideways pressure ✗ What We Know So Far: Glass has multiple weakness problems that matter for construction What We Don't Know Yet: Any solutions to these problems |
| Protective coatings are one way to give glass greater strength, although this can affect transparency, one of the main reasons for using glass. | What it says: Coatings help strength but hurt see-through quality What it does: Introduces the FIRST solution attempt, with its trade-off Source/Type: Factual statement about a solution approach Connection to Previous Sentences: MAJOR SHIFT - After 3 sentences of problems, we now get our first solution Visualization: Uncoated glass: 60% strong, 95% clear vs. Coated glass: 85% strong, 70% clear Reading Strategy Insight: The passage is now moving into "solutions" mode - expect more solution attempts |
| Also, altering the composition of the glass can make it harder for cracks to form, but this alteration can mean loss of other desirable properties, or make the glass more expensive to manufacture. | What it says: Changing glass recipe helps with cracks but creates other problems What it does: Presents the SECOND solution attempt, again with trade-offs Source/Type: Factual statement about another solution approach Connection to Previous Sentences: This follows the EXACT same pattern as sentence 4 - solution + but + trade-off Visualization: Regular glass: cheap, some cracks vs. Altered glass: expensive, fewer cracks, worse in other ways Reading Strategy Insight: Feel confident here - this is just repeating the pattern from sentence 4, not adding complexity |
2. Passage Summary:
Author's Purpose:
To explain the challenges of using glass in construction and describe the various solutions that have been developed to address these problems.
Summary of Passage Structure:
In this passage, the author walks us through the glass strength problem and the engineering solutions that address it:
- First, the author establishes the core problem - that glass starts strong but becomes weak very easily, especially when used for building structures
- Next, the author presents early solution attempts like protective coatings and changing glass recipes, but shows these create trade-offs like losing transparency or increasing costs
- Then, the author explains manufacturing solutions, particularly tempering processes that make glass stronger and safer when it breaks, with detailed explanations of both heat and chemical tempering methods
- Finally, the author discusses laminated glass as another structural solution, but concludes by showing that even this advanced approach creates significant manufacturing challenges
Main Point:
While engineers have developed multiple ways to make glass stronger for construction use - including coatings, composition changes, tempering, and lamination - each solution comes with its own set of trade-offs and complications, making structural glass applications persistently challenging.
1. Question Analysis:
This is a word-in-context question asking us to find the term that would LEAST alter the meaning if substituted for "integrity" in the highlighted sentence: "Use of laminated glass in a structure helps to maintain the structure's integrity in the event that the glass breaks."
Connecting to Our Passage Analysis:
From our analysis, we know that:
- The sentence introduces laminated glass as a solution for structural applications
- The context is about what happens "in the event that the glass breaks" - so we're talking about maintaining something important when failure occurs
- The passage has been focused on structural applications and safety concerns
- The following sentences explain that lamination "adds strength and keeps large broken pieces from shattering" and prevents "potentially destructive stresses in the assembled structure"
Prethinking:
In this structural context, "integrity" refers to the building or structure remaining stable, safe, and functional even when the glass component fails. We need a word that captures this sense of structural stability and soundness. The word should convey that the essential structural properties are preserved despite component failure.
• "Completeness" suggests all parts are present and whole, but the passage is specifically about what happens when glass breaks (becomes incomplete)
• The context is about functionality during failure, not about having all original components intact
• Doesn't capture the structural stability concept that's central to the passage's focus on construction applications
Common Student Mistakes:
1. Don't buildings need to be "complete" to work properly?
→ The passage specifically discusses what happens when components fail - the goal is maintaining function despite incompleteness
1. Isn't keeping all the glass pieces together about completeness?
→ The focus is on preventing structural collapse and injury, not on keeping every piece in its original position
• "Conformity" relates to meeting standards or matching specifications, which isn't the focus here
• The passage is about maintaining structural stability during failure, not about adherence to building codes
• Doesn't address the safety and stability concerns that dominate the structural glass discussion
Common Student Mistakes:
1. Don't structures need to conform to safety standards?
→ While true, the sentence is about what happens during glass breakage, not about meeting design specifications
1. Isn't maintaining conformity important in construction?
→ The context is emergency performance (when glass breaks), not normal operational compliance
• "High quality" is too vague and doesn't specifically address structural stability
• The passage isn't focused on quality levels but on functional performance during component failure
• Doesn't capture the specific engineering concept of structural integrity under stress
Common Student Mistakes:
1. Wouldn't maintaining high quality be important for buildings?
→ The passage is specifically about emergency scenarios (glass breaking), not general quality maintenance
1. Don't all the solutions mentioned aim to improve quality?
→ The solutions target specific problems (strength, safety, crack prevention) rather than general quality
• "Soundness" directly relates to structural stability and the ability to remain safe and functional
• Perfectly captures the engineering concept of maintaining structural performance during component failure
• Aligns with the passage's emphasis on safety and preventing "potentially destructive stresses in the assembled structure"
• Fits the context of what happens when glass breaks - the structure needs to remain sound/stable
Key Evidence: "This adds strength and keeps large broken pieces from shattering" and "precise measurements and extremely small margins of error are needed to avoid potentially destructive stresses in the assembled structure" - both support the concept of maintaining structural soundness.
• "Complexity" refers to how intricate or sophisticated something is, which is unrelated to structural performance
• The passage discusses simplifying some processes (like the air-cooling method for laptop displays)
• Maintaining complexity during glass breakage makes no sense in this structural context
Common Student Mistakes:
1. Isn't the passage about complex engineering solutions?
→ While the solutions are complex, the goal is maintaining structural stability, not preserving complexity itself
1. Don't laminated glass systems add complexity that needs to be maintained?
→ The sentence is about what happens when the glass breaks - complexity becomes irrelevant if the structure collapses