MCQs on Plastic
8 questions. Tap an option to check it instantly, then read the solution.
Answer: C. water proofing
Polyethylene (PE) and Polyvinyl Chloride (PVC) are plastics known for their excellent resistance to moisture. They are non-porous and are widely used to manufacture pipes, sheets, and membranes for waterproofing applications in construction.
Answer: D. They possess low coefficient of expansion as compared to cast-iron or galvanized-iron pipes.
This statement is false. Plastics, including PVC, have a significantly higher coefficient of thermal expansion than metals like cast iron or steel. This means they expand and contract much more with temperature changes, which must be accounted for during installation.
Answer: B. A mixture of cement and asphalt
Plastic asphalt, often used for roofing and waterproofing, is a composite material made by mixing asphalt with fillers. While various fillers can be used, it is commonly a mixture of cement (or other minerals) and asphalt, which gives it a thicker, more plastic consistency.
Answer: D. Bakelite
Thermoplastics (like polyethylene, nylon, and PVC) can be repeatedly softened by heating and hardened by cooling. Bakelite, however, is a thermosetting plastic. Once it is cured and hardened, it cannot be remelted or reshaped.
Answer: D. Virgin Plastic
Virgin plastic is the term for direct-from-petrochemical-source plastic resin that has not been recycled or mixed with other materials like reinforcements. A composite is a material made from two or more constituent materials with significantly different properties.
Answer: B. Polyvinyl chloride plastics
Polyvinyl chloride (PVC) is inherently flame retardant due to its chlorine content. It is difficult to ignite and tends to self-extinguish when the flame source is removed, making it effectively non-inflammable compared to many other common plastics.
Answer: B. polymeric materials
Plastics are a major class of synthetic or semi-synthetic materials that are made up of polymers. A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Therefore, plastics are prime examples of polymeric materials.
Answer: D. Tempering
Laminating, blowing (blow molding), and calendaring are all common industrial processes for shaping and fabricating plastic articles. Tempering is a heat treatment process used to increase the toughness of metals and glass; it is not used for plastics.