Why Is a Styrofoam Cup Cooler to the Touch Than a China Cup?

AI Thread Summary
Styrofoam cups feel cooler to the touch than china cups because they are poor heat conductors. The foam's structure, filled with air bubbles, significantly impedes convection, while the plastic material itself does not transfer heat efficiently. This combination results in less heat being conducted to the outside surface of the cup. Consequently, even when filled with hot liquids, styrofoam remains comfortable to hold. Understanding these properties explains why styrofoam is often preferred for hot beverages in casual settings.
Gringo123
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The other day I was at a football match and I had a cup of tea in a styrofoam cup. The tea was practically boiling - far too hot to drink, but the cup was only warm to the touch. I know that if the tea had been in a china cup or mug it would hve been uncomfortably hot to pick up.
Why does the styrofoam cup not transfer heat very well?. Is it because convection is impeded by all the air bubbles inside the foam or is it because the plastic material from which it is made is not a good conductor of heat? (or is it a combination of the 2?)
 
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It is the combination of two.
 

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