Social Science (087) — AI-generated practice question

Property: Aluminium is light (low density) compared to steel.

Why it matters for aircraft: Every kilogram saved in an aircraft's structure directly reduces fuel consumption and allows a greater payload. Lightness is therefore critical in aircraft manufacturing, where weight is a primary design constraint.

Why it is less decisive for bridges: Bridges are fixed structures that must bear enormous static loads and withstand stress over decades. For such structures, tensile strength, rigidity and load-bearing capacity are far more important than weight, making steel the preferred choice despite being heavier.

Source: Manufacturing Industries, Chapter 6 (Aluminium Smelting section)

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• The passage states aluminium is "light" and used to "manufacture aircraft" — directly supporting the answer.
• The key examiner expectation: name the property (lightness), explain why it is vital for aircraft, then contrast with bridges where strength/rigidity matters more than weight. Many students name the property but forget the contrast — that contrast is worth the third mark.
• Avoid listing all properties; the question asks for one property only.