Question
How does tea in a thermo flask remain hot for a long time?
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Answer
The air between the two walls of the thermo flask is evacưated. This prevents heat loss due to conduction and convection.
The loss of heat due to radiation is minimised by silvering the inside surface of the double wall. As the loss of heat due to the three processes is minimised and the tea remains hot for a long time.
The loss of heat due to radiation is minimised by silvering the inside surface of the double wall. As the loss of heat due to the three processes is minimised and the tea remains hot for a long time.
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