Resistance of Non-Conductors: Temperature Effects

AI Thread Summary
The resistance of non-conductors, such as bricks, behaves differently than that of conductors like wires. While the resistance of conductive materials typically increases with temperature due to electron scattering, non-conductors exhibit a decrease in resistance as temperature rises. This is attributed to thermal agitation that can free electrons from atoms, allowing for current flow under certain conditions. Resources for finding resistance values of various materials include Google, matweb.com, and the CRC Handbook of Physics and Chemistry. Understanding these differences is crucial for applications involving temperature effects on material resistance.
AdmiralZ
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How does the resistance of a non-conductor, eg. a brick change with temperature. Does it conform to the wire where resistance increases with temperature, or is it different?
 
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For non conducting materials, resistance would decrease with temperature. Heat is, more or less, agitation of molecules in a substance. If the temperature is great enough, electrons can be ripped from the atoms, thus allowing a current to flow.
 
It is very different. A "wire" is usually a conductor, whose resistivity increases with temperature due to increased scattering off the positive ions. A brick is usually an insulator (at room temp) whose resistivity decreases on heating, due to thermal excitations.
Look at this : https://www.physicsforums.com/showthread.php?t=72062&highlight=brick
 
Thanks guys. Also, would any of you happen to know of a site where I could find the resistances for certain objects?
 
1. Google
2. matweb.com
3. CRC Handbook of Physics and Chemistry (universities usually have access to an online version)
 
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