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Homework Help: Quick voltage question

  1. Mar 5, 2005 #1
    Hi all, I am asking to see if I understand voltage correctly:
    This is what circuit looks like:
    Code (Text):

    |           +      |
    Vs         v(t)    |
    |           -      |
    |_________B_______ |
    As I see it, v(t)(voltage drop from A to B) is voltage across R2, is it correct?
    Thank in advance.
  2. jcsd
  3. Mar 5, 2005 #2
    that is correct
  4. Mar 5, 2005 #3
    What? the sum of the voltage drop from R1 and R2 is equal to the EMF (battery).
  5. Mar 5, 2005 #4
    Didn't want to start another thread, but now I have another question: after the switch in some circuit moves to a certain position I get following circuit:
    Code (Text):

                    |        |
                    |        |
                 indctr     R2
                    |        |
                    |        |
    Then voltage drop from A to B is sum of voltages across R1 and inductor (or R2), right? Then there is a current coming from A and divides into 2 (for inductor and R2)? Or does R1 not have any current?
    Thanks again.
    Last edited: Mar 5, 2005
  6. Mar 5, 2005 #5
    drop from A to B is Vr1 and 2*Vr2. Even though the inductor and r2 voltages are the same, they both must be added.
  7. Mar 5, 2005 #6
    Why 2*VR2? they are in parallel. What am I missing here? Don't inductor and R2 follow KVL?
  8. Mar 5, 2005 #7
    oops, my bad. youre right. its just one.
  9. Mar 5, 2005 #8
    Oh, Ok, thanks!
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