Question

Answer the questions briefly

Answer 1

Thermos flask consists of a glass vessel with double walls. since the vessel is made of glass heat loss by conduction is prevented. There is a vacuum between the two walls, which prevents heat loss by conduction and convection. The outer surface of the inner wall and the inner surface of the outer wall are silvered. The shiny surfave reduces heat loss by radiation. The mouth of the vessel is closed by a cork to prevent evaporation from hot liquids. It also prevents heat loss by evaporation from hot liquids. The vessel is kept on a cork pad to keep it thermally insulated. Thus, a thermos flask prevents heat transfer from taking place, and keeps hot things hoat and cold thing cold foe long periods