Why are ceramics cold to touch and plastics warm?

Too hot to touch, too cold to scald.


Asked by: Geoff Dunwell, Maidenhead

Objects feel warm or cold because of the rate and direction at which heat flows between them and our fingers. That, in turn, depends on the thermal conductivity of the material they’re made of. Plastic’s thermal conductivity is around 10 times lower than ceramic’s. This relatively sluggish transfer of heat is what makes plastic feel ‘warmer’ than ceramic, even if they’re at the same temperature.

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