Question
Why felt is used for thermal insulation in preference to air?
Solution
Dry air is a bad conductor but heat can be transferred into air by means of convection and radiations.
Felt is a fine fibrous fluffy material having numerous pores which trap a lot of air.
But, air molecules cannot move freely and consequently convection is not possible in felt. That is why felt is used for thermal insulation in preference to air.
Felt is a fine fibrous fluffy material having numerous pores which trap a lot of air.
But, air molecules cannot move freely and consequently convection is not possible in felt. That is why felt is used for thermal insulation in preference to air.
