Assessment and Qualifications Alliance (AQA) GCSE Engineering Practice Exam

The material most commonly used for the casing of a handheld vacuum is polycarbonate. This is due to its excellent strength-to-weight ratio, durability, and impact resistance, making it ideal for creating sturdy and lightweight vacuum casings that can withstand the rigors of daily use. Polycarbonate is also resistant to shattering, which enhances safety and longevity in consumer products.

Other materials mentioned, such as polyethylene terephthalate, polyvinyl chloride, and low-density polyethylene, have different properties and applications. While they may be used in various other products, their characteristics do not make them ideal for the specific demands of a handheld vacuum casing, where durability and impact resistance are critical.