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Resistance and Current flow

  1. Sep 5, 2014 #1
    1. The problem statement, all variables and given/known data

    A current-carrying ohmic metal wire has a cross-sectional area that gradually becomes smaller from one end of the wire to the other. How does the current vary along the length of the wire?

    2. Relevant equations

    a. It increases.
    b. It remains constant.
    c. It decreases.

    The answer give is (A).. Im a bit confused, as my understanding is the resistance will increase in the wire, but the current should be constant through it as to not accumulate any charge in the wire.. So the wires resistance increases, and the drift speed of the electrons increase to maintain the constant current through the wire?? Do you think the questions is meant to ask, how does the driftspeed/resistance vary along the length?
  2. jcsd
  3. Sep 5, 2014 #2


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    Homework Helper

    You are right, the current is the same along the wire. The resistivity increases.

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