Class 8 | Science | Ch 3 | Synthetic Fibres and Plastics | NCERT Solutions 1. Explain why some fibres are called synthetic. Answer: Those fibres which are prepared by man using chemicals are called synthetic fibres. They are formed by combination of large number of small molecules joined together. For ex: Rayon, nylon, polyester, acrylic etc. 2. Mark (√ ) the … [Read more...] about Chapter 3 Synthetic Fibres and Plastics