SC-1366
Conduction
Lower Sec Science · Secondary 2 · Medium · Conduction
A double-walled flask has air trapped between its walls. Why does the trapped air help to keep hot soup warm for a longer time?
- Air is a poor conductor of heat, so it slows down heat loss by conduction.
- Air is a good conductor of heat, so it quickly spreads heat around.
- Air reflects all heat radiation back to the soup.
- Air cools the soup by increasing convection currents.
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