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Homework Help: Question anyone dare to answer?

  1. Dec 27, 2004 #1
    Question. Anyone dare to answer?

    Question1: A uniform electric field is parallel to the x-axis. Inwhat direction can a charge be displace in this field without any external work being done on the charge?

    Question2: Why is it that under static conditions, all points in a conductor must be at the same electric potential?

    Happy answering & happy new year! :rofl:
    Last edited: Dec 27, 2004
  2. jcsd
  3. Dec 28, 2004 #2

    Andrew Mason

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    Homework Helper

    The definition of work is [itex]W = \vec F \cdot \vec d = qE cos\theta d[/itex]. So if no work is done, the displacement must be in the direction perpendicular to the force ie [itex] cos\theta = 0 \rightarrow \theta = \pi/2[/itex]

    In a conductor, the population of free electrons are free to move. So a free electron will move if there is an electric potential difference between it and another charge. So if there is no motion, there can be no potential difference between charges.

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