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How voltage travels in wire

  1. Jun 22, 2008 #1
    I would like to know if there was a supply voltage of 20 volts (just voltage no current) on an input terminal. And there is a ground terminal and an output terminal. Will the 20 volts just be concentrated on the ground terminal where the connection is complete or will all terminal have a voltage of 20 volts.
  2. jcsd
  3. Jun 22, 2008 #2


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    The voltage is a statepoint, so voltage does not travel down a wire, but voltage increases or decreases along a wire depending on direction one travels along the wire or how close to the voltage source one is.

    The current travels along the wire, and there is a voltage drop (gradient) associated with the current. The voltage drop is simply the product of the current and resistance over the length of the wire. The greatest resistance is usually found in a resistor or load as compared to conductor or wire which have low resistance.

    One can short circuit a battery, which will cause it to get very hot as the current is very high and the chemical reaction is very rapid, and then internal resistance of the battery will increase.

    If there is no current, the conductor attached to the output terminal will be 20 V above ground, assuming the ground is at the - battery terminal.
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