Which non-ferrous metal is known for being lightweight and used in aerospace due to strength-to-weight ratio?

• A. Aluminium
• B. Titanium
• C. Copper
• D. Tin

Answer: (B)

The idea being tested is strength relative to weight, or specific strength, which is crucial in aerospace where you want parts that are strong but as light as possible. Titanium stands out here because it combines high tensile strength with a moderate density, giving a very high strength-to-weight ratio. It also resists corrosion and maintains strength at elevated temperatures, which are important in aircraft engines and airframes. While aluminum is also lightweight and widely used, its strength-to-weight ratio is lower than titanium’s in many demanding applications, especially where heat and long-term stress are concerns. Copper and tin are heavier or not strong enough for structural, weight-critical parts, so they don’t fit the aerospace needs as well. So the metal best known for being lightweight and, due to its strength-to-weight ratio, used in aerospace is titanium.