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Doubt regarding conduction.

  1. Oct 27, 2012 #1
    We know, heat transfer in a material happens due to vibration or vigorous to and fro movement of particles. Also, the density of wood is much more less than the density of iron i.e, distance between particles is more. Thus, particles in wood has more space to vibrate vigorously than the particles of iron. Why is iron better conductor of heat than wood? Does conduction of heat depend on density of a material? (OR) On what exactly does the conduction of heat depend on?
     
  2. jcsd
  3. Oct 27, 2012 #2
    My guess is that in metal, it is easier for particles to influence one another. The heat gets transferred better because there aren't as many empty-space barriers.
     
  4. Oct 27, 2012 #3
    So you think that if density is more conduction is more. Compare air and wood. Air is better conductor than wood.
     
  5. Oct 27, 2012 #4

    haruspex

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    Metals conduct heat well for the same reason they conduct electricity - it's the free electrons. The best metal conductors are those in which electrons can move relatively freely, typically pure metals in a crystalline state rather than alloys.
    In non-metallic crystals, lattice vibration is key.
    Air conducts heat very poorly, but it does convect, which a solid cannot.
     
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