Why does glass feel as cold as metal despite being non-conductive?

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Discussion Overview

The discussion explores why glass, despite being a poor conductor of electricity, feels as cold as metal when touched, even at the same low temperature. It examines the relationship between thermal and electrical conductivity, focusing on the properties of different materials.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant notes that materials with higher thermal conductivity feel colder at the same temperature due to their ability to transfer heat more effectively.
  • Another participant questions the relationship between heat conduction and electrical conduction.
  • A participant suggests that both heat and electrical conduction are based on similar properties, but this is challenged by another who clarifies that heat conduction occurs via phonons, while electrical conduction relies on free electrons.
  • A later reply highlights that materials like diamond can conduct heat very well while being poor electrical conductors, illustrating the difference between the two types of conduction.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between heat and electrical conduction, with some agreeing on the distinction while others propose a connection. The discussion remains unresolved regarding the broader implications of these properties.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the properties of materials and the definitions of conductivity types. Some mathematical or physical principles underlying these concepts are not fully explored.

lennybogzy
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If I touch a variety of materials all at the same low temperature, such as wood, metal, bronze, plastic - the most conductive will clearly feel the coldest (even as they're all at the same temp) because those materials are able to transfer heat and conduct with less thermal or electrical resistance.

but what about glass? glass isn't conductive at all, in fact high power resistors are made from cermaics - but it feels just as cold as metal

what gives?
 
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You are asking about the correlation of heat- vs. electric conduction?
 
my understanding was that both conduction of heat, and conduction of electrons are based on the same properties...
 
lennybogzy said:
my understanding was that both conduction of heat, and conduction of electrons are based on the same properties...
Not really.
Conduction of heat s by phonons, vibrations of the atoms in a material. Conduction of electricity is based on free electrons.
Crystals and metals have stiff bonds between atoms which allow the vibrations to conduct heat well, but only metals have the free electrons to conduct electricty.
The most extreme example of this is diamond, it is the best conductor of heat compared to the worst conductor of electricity.
 
awesome. perfect answer.
 
diamond is also the hardest material ;-)
 

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