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Current Flowing Through RC Circuit (Charging)

  1. Oct 6, 2008 #1
    Hey, everyone. Just a quick question here. If I have the following circuit, with it's switch initially opened, what will happen to the current through resistors 1 and 2, after I close the switch?

    http://img249.imageshack.us/img249/7716/showmeplkh6.gif [Broken]

    1) When the switch is first closed, the magnitude of the current through R1 is ______ and the magnitude of the current through R2 is ______.

    My answer is: non-zero, non-zero

    My friend thinks: zero, non-zero

    Now, we are having a debate over this question. We both agree that the current through R2 is definitely non-zero; however we disagree on the current through R1.

    I think that there should be current through R1 because the capacitor has to get charged somehow.

    What do you think?

    Thanx in advance.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Oct 6, 2008 #2
    whats the voltage drop through c2 and c3 at that time?
  4. Oct 6, 2008 #3
    Thank you for your question granpa :D !

    You have to think of the resistor R1 as a resistor who is connected in parallel to Capacitor C2,3. Therefore the voltage across the resistor and the capacitor, immediately after the switch is closed, must be zero.

    Gotta love physics <3
  5. Oct 8, 2008 #4


    Staff: Mentor

    Then by Ohms law what is the current if the voltage is zero?
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