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Homework Help: Definition of Voltage

  1. Oct 18, 2013 #1
    1. The problem statement, all variables and given/known data
    If KVL was not true, would our definition of Voltage still make sense? Clearly explain and prove your answer

    2. Relevant equations
    KVL definition
    Voltage definition

    3. The attempt at a solution
    I said no, because if KVL were not true, then definition of voltage would not make sense. By the law of energy conservation, Energy input = energy output( i may be wrong? but intuitive to me, since a circuit is a closed system). Since voltage by definition is the energy required to move 1C of charge from 1 node to another. The sum of voltages in a closed system must equal 0, since a system cannot have excess energy, as it must be either used,stored or dissipated

    Thoughts guys? Proff made this question, and ive never come across a theoretical question like this in a engineering course
  2. jcsd
  3. Oct 18, 2013 #2

    Simon Bridge

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    You need a statement of the definition of voltage.
  4. Oct 18, 2013 #3
    The definition my proff gave me is this: Voltage is the energy required to move 1c of charge from 1 node to another
  5. Oct 18, 2013 #4

    Simon Bridge

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    Generally - one volt is the energy required to move 1 coulomb from one node to the next... what if there is a battery between the two nodes? What if the end node is the same as the start node?

    The next step is a statement of what KVL says ... then you want to relate the two.
    The KVL requires a specific property of the electric field - besides energy conservation - do you know what it is?

    Anyway - the patter for these things is:
    1. definition of voltage
    2. statement of KVL
    3. what does 2 say about 1.
    4. if 2. is wrong, what does that say about 1.

    For the record: you have the right idea - but you were instructed to be clear.
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