Question

why do we use thermos flask

Answer 1

Explanation:

The technical name of a thermos is a vacuum flask (you will know the reason why, shortly). To keep your drinks hot or cold, it minimizes heat transfer due to conduction and radiation. Convection is not included because convection keeps the temperature in a liquid even.

Answer 2

Answer:

to keep the things inside it at same temperature.

Explanation:

in thermos, the system is closed system. therefore no energy and heat is exchanged. hence the solid inside it remain at same temperature as it was filled