Question

Explain how conduction , convection and radiation are minimised in a Thermos flask

Answer 1

Answer:

The thermos flask consists of a double-walled glass vessel resting on a cork inside a metal or plastic case. The outer surface of its inner wall and the inner surface of its outer wall are silvered. This prevents heat transfer due to radiation. ... The double-walled glass vessel and vacuum prevents heat loss by conduction.

Answer 2

Answer:

The silver coating on the inner bottle prevents heat transfer by radiation, and the vacuum between its double wall prevents heat moving by convection. The thinness of the glass walls stops heat entering or leaving the flask by conduction. The case surrounding the flask provides additional insulation.