Question

explain about plastic case in termos flask

Answer 1

Here is your answer buddy!!!

The flask is placed on a cork in a metal case and is secured at the neck with a ring of rubber. Heat from a hot liquid in the thermos flask cannot escape from it by conduction or convection as there is vacuum between the two walls of the glass vessel.

Hope it helps!!!!????

Answer 2

Inside a thermos is glass, and around the glass is a vacuum. The glass envelope is fragile, so it is encased in a plastic or metal case