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Homework Help: Circuit Help (Parallel, finding IR1, VR1, etc )

  1. Nov 21, 2004 #1
  2. jcsd
  3. Nov 21, 2004 #2
    go in loops aroun the circuit and figure it out

    the least you can do is show us you attempted it in the least
  4. Nov 21, 2004 #3
    I dont understand how to find the Vr and Ir.

    Im in this electricity class in highschool and the only thing I can almost get out of this is the Rt.

    I am so confused and I have to get this done in about 30 mins...
  5. Nov 21, 2004 #4
    What equations have you been given for these things?
  6. Nov 21, 2004 #5
    Nothing, I just have to find the blanks...

    My teacher isn't bad he just doesnt teach the way he should...

    And Im still very confused and stressed about this.
  7. Nov 21, 2004 #6
    For the first one

    for R1 and R2 find the equivalent resistance of R1 and R2 and R4 and R5

    now that you have three resistors in series find the equivalent resistance of the 3 resistors in series

    now find the current thorugh all of them

    now that you ahev current through all of them you can figure out the I R3 part

    for the resistors R1 and R2 what can be said about the voltage and current across them? Use this property to figure out the IR values across each of them Similarly for R4 and R5

    once you have all the values for current you can figure out the voltages across each resistor
  8. Nov 21, 2004 #7
    For the first one... Equivalent of R1 and R2 is 500ohms, and R4 and R5 would be 2.8k ohms... right?

    The Rt would 4.8E3?

    Im not sure how to find the current without voltage... And if your wondering how Im getting these answers Im using

    1 1
    _ + _
    R1 R2


    Am I right so far?
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