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Capacitor discharge question

  1. Dec 2, 2011 #1
    In this scenario, C2 is charged to 100V and C1 to 0V. Wouldn't the current go in the other direction, unless I misunderstood something? The only reason I can see why the current is displayed in this direction is because we're asked to find V2(t), and doing it this way you'd find a negative V2 and it would "help" us see that we can have the rest of the equation equal to V2(t).

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  2. jcsd
  3. Dec 2, 2011 #2


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    yes, you are correct. It really doesn't matter which way you draw voltage and current, as long as you get the right answer (negative if your arrow points the "wrong" way)
  4. Dec 2, 2011 #3
    agreed. You will get -v2(t) result. Typically diagrams are drawn with arbitrary direction of current. And once you find the value to be negative it simply implies the original direction of arrow is wrong and simply needs to be reversed.
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