''A hot liquid' remains hot and a cold liquid remains cold in a thermos flask.'' Explain how ?

''A hot liquid' remains hot and a cold liquid remains cold in a thermo

1.	''A hot liquid' remains hot and a cold liquid remains cold in a thermos flask.'' Explain how ?
Answer» Solution :Between the TWO walls of a THERMOS flask VACUUM is created, so tehre is no exchange of heat between the liquid and outside air. The SURFACE is made shinning to reduce loss of heat by radiation. Loss of heat by conduction and convection is also minimised.