Question

The windows of an airplane are made in

• A. PVC
• B. PTFE
• C. PMMA
• D. PEEK

Hint:

PMMA (Acrylic) is used in airplane windows due to its lightweight nature, high impact resistance, and excellent optical transparency.

Answer 1

The Correct Option is C

Airplane windows are designed to withstand high pressure differences, impact forces, and extreme environmental conditions. The material used must be transparent, lightweight, strong, and impact-resistant.
Step 1: Understanding the Materials - PVC (Polyvinyl Chloride): Mostly used for pipes and flooring, but it lacks the required optical clarity and impact resistance for airplane windows.
- PTFE (Polytetrafluoroethylene): Known for non-stick properties (e.g., Teflon), but it is not transparent or rigid enough for windows.
- PMMA (Polymethyl Methacrylate): Also known as Acrylic or Plexiglass, it is widely used in aircraft windows due to its high transparency, impact resistance, and lightweight nature.
- PEEK (Polyether Ether Ketone): A high-performance polymer used in aerospace components but not suitable for transparent applications like windows.


Step 2: Evaluating the Options - Option (A) - Incorrect: PVC is not suitable for windows due to its opacity and fragility.
- Option (B) - Incorrect: PTFE is not transparent and lacks mechanical strength.
- Option (C) - Correct: PMMA is widely used in airplane windows due to its high strength and optical clarity.
- Option (D) - Incorrect: PEEK is used in structural components but not in windows.


Step 3: Conclusion Since PMMA (Acrylic/Plexiglass) is the standard material for airplane windows, the correct answer is option (C).