Question

explain the construction and working at of a thermos flask how does it minimise the loss of heat

Answer 1

How does a thermos flask prevent the loss of heat?These few, simple features prevent virtually all heat transfer by either conduction, convection, or radiation. The vacuum prevents conduction. The tight stopper prevents air from entering or leaving the flask, so convection isn't possible either.

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Answer 2

These few, simple features prevent virtually all heat transfer by either conduction, convection, or radiation. The vacuum prevents conduction. The tight stopper prevents air from entering or leaving the flask, so convection isn't possible either.

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