14. What is the density of plastic?
This mechanical engineering interview question has many possible answers as there are different types of plastics, and all of them have their different density. It is calculated by dividing the mass of the product by its volume. The most common one is polypropylene which has a density of 0.92 grams per cubic centimetre. The other common type of plastic is Polyvinyl Chloride (PVC) which has a density of 1.38 grams per cubic centimetre, and Polyamide has a density of 1.15 grams per cubic centimetre. Polythene has three different types, which is categorized on its density itself.
