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[Drift velocity] Factors affecting velocity

  1. May 27, 2012 #1
    1. Is the charge density (No. of charges/volume) constant for a specific material ? e.g. Copper has a constant charge density no matter how big it is ?

    2. Why someone told me that increasing the cross-sectional area of a wire will not affect its drift velocity ? The resistance will be reduced and the electrons can move faster, isn't it ?
  2. jcsd
  3. May 27, 2012 #2


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    You need to learn the difference between "resistance" and "resistivity". This is the same as the issue between "mass" and "density". One requires the knowledge of a volume of the object, the other doesn't.

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