Researchers conducted an experiment to determine how much cooler the air would be in and around a building with a...
GMAT Multi Source Reasoning : (MSR) Questions
Researchers conducted an experiment to determine how much cooler the air would be in and around a building with a highly reflective roof surface, as compared to the air in and around a building with a dark roof surface. The researchers constructed four identical small structures, with the exception that each structure had a different type of material for its roof. Each structure had a roof made of exactly one of the following four roofing materials: tin painted silver, tin painted white, black asphalt shingles, and asphalt shingles painted white. At a time when the outside air was 25°C, the following measurements were taken: roof surface temperature, air temperature six inches above the structure, and air temperature inside the structure.
The researchers hypothesized that, for each category, the structure with the white asphalt shingles would have the lowest temperatures, the structure with the white tin would have the second lowest temperatures, the structure with the black asphalt shingles would have the highest temperature, and the structure with the silver tin would have the second highest temperatures.
For each of the following roofing materials, select Consistent if the temperature measurement taken on the roof surface for that material (in relation to the other temperature measurements) was consistent with the researchers' hypothesis. Otherwise, select Not consistent.
Owning the Dataset
Understanding Source A: Text Source - Experimental Design
| Information from Dataset | Analysis |
|---|---|
| ""Researchers conducted an experiment to determine how much cooler the air would be in and around a building with a highly reflective roof surface, as compared to the air in and around a building with a dark roof surface."" |
|
| ""four identical small structures, with the exception that each structure had a different type of material for its roof"" |
|
| ""tin painted silver, tin painted white, black asphalt shingles, and asphalt shingles painted white"" |
|
| ""At a time when the outside air was 25°C, the following measurements were taken: roof surface temperature, air temperature six inches above the structure, and air temperature inside the structure"" |
|
| ""researchers hypothesized that, for each category, the structure with the white asphalt shingles would have the lowest temperatures, the structure with the white tin would have the second lowest temperatures, the structure with the black asphalt shingles would have the highest temperature, and the structure with the silver tin would have the second highest temperatures"" |
|
- Researchers designed a controlled experiment testing four roof types (varying both material and color)
- Measured how different roofs affect air temperatures at three locations
- Predicted white-painted shingles would perform best
Understanding Source B: Visual Source - Temperature Results Chart
Chart Analysis:
- The chart shows temperature measurements for all four roofing types at three locations
- Key patterns observed:
- White shingles produced the coolest air temperatures (23°C above, 22°C inside)
- Black shingles produced the hottest conditions overall (30°C above, 30°C inside, 68°C surface)
- Surface temperatures showed extreme variation (45°C range from 23°C to 68°C)
- Silver tin had the coolest surface (23°C) but didn't produce the coolest air
- Key findings:
- White shingles created air temperatures below the 25°C ambient baseline (cooling effect of 2-3°C)
- Surface temperature patterns don't match air temperature patterns
- Connection to Source A:
- Results partially confirm the hypothesis - white shingles did produce the coolest air temperatures as predicted
- Surface temperature results contradict the hypothesis - silver tin had the coolest surface instead of being second hottest as predicted
- The extreme 45°C surface temperature range demonstrates the dramatic differences between reflective and dark surfaces
- White shingles achieved the best air cooling as partially predicted
- Surface temperatures behaved completely differently than expected
- Silver tin had the coolest surface despite not producing the coolest air
Overall Analysis
- The roofing experiment successfully measured how different roof materials and colors affect temperatures
- Researchers correctly predicted that white shingles would produce the coolest air temperatures (achieving 2-3°C below ambient)
- Their surface temperature predictions were wrong - silver tin had the coolest surface, not white shingles
- Key finding: Effective air cooling doesn't necessarily correlate with surface temperature
- Material properties affect heat transfer in complex ways that can't be predicted by color alone
Temperature Rankings Analysis
Hypothesized Order (lowest to highest):
- White asphalt shingles (lowest)
- White tin (second lowest)
- Silver tin (second highest)
- Black asphalt shingles (highest)
Actual Air Temperature Results:
- Above air: White shingles (23°C) < White tin (27°C) < Silver tin (29°C) < Black shingles (30°C)
- Inside air: White shingles (22°C) < White tin (25°C) < Silver tin (26°C) < Black shingles (30°C)
- Air temperature hypothesis: Completely confirmed
Actual Surface Temperature Results:
- Surface order: Silver tin (23°C) < White shingles (29°C) < White tin (31°C) < Black shingles (68°C)
- Surface temperature analysis:
- Black shingles: Hypothesized highest, actually highest (68°C) - Consistent
- White shingles: Hypothesized lowest, actually second lowest (29°C) - Not consistent
- Silver tin: Hypothesized second highest, actually lowest (23°C) - Not consistent
Final Results
- Black shingles: Consistent with hypothesis
- White shingles: Not consistent with hypothesis
- Silver tin: Not consistent with hypothesis
Black shingles
White shingles
Silver tin