Question

Why do we prefer to use 2 thin blankets instead of a thick blanket?

Answer 1

Air is trapped in the space between two thin blankets. Since air is an insulator of heat, it prevents the escape of body heat.

Answer 2

Answer:

warmer underneath two blankets due to air layer between them.

Explanation:

When we use two thin blankets with the total thickness equaling the thickness of the single thick blanket we can get better shielding from cold outside.

There is a thin layer of air between two thin blankets. That prevents heat transfer in either direction.  Air is a good insulator. The main way of heat transfer in air is by radiation.

In a blanket the heat is transferred by conduction.

Further it is more convenient too to use two thin blankets. One single thick blanket is heavy, uncomfortable, and unmanageable too.