Question

Why is it advised to wear more layers of woolen clothes rather than just one thick woolen cloth to keep us warm in winter?

1. Air trapped between layers of woolen clothes acts as an insulator of heat
2. Layers of clothes produce heat
3. Air trapped between layers of woolen clothes acts as a conductor of heat

Answer 1

Having more layers of clothing keep us warmer in winters as they have a space between them. That space gets filled up with air. Air acts as an insulator of heat, preventing our body heat from escaping in the surroundings.
Hence, wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.