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Circuit Diagram

  1. Sep 27, 2009 #1
    1. The problem statement, all variables and given/known data

    For the circuit shown, if v2 = 1000i2 and i2 = 5 mA, determine vs.


    2. Relevant equations

    [tex]5 mA = 0.005 A[/tex]
    [tex]P = v_{2}i[/tex]

    3. The attempt at a solution

    [tex]P = v_{2}i[/tex]

    [tex]v_{2} = \frac{P}{I} = \frac{5}{0.005} = 1000 V[/tex]

    [tex]v_{2} = 5v_{1}[/tex]

    [tex]v_{1} = \frac{v_{2}}{5} = \frac{1000}{5} = 200 V[/tex]

    What I am having problems with is [tex]v_{s}[/tex] is a independent voltage source so I am not sure what to do.
  2. jcsd
  3. Sep 27, 2009 #2


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    Homework Helper

    Hi Killer. I'd like to help but I don't understand the symbols in your diagram. What is the circle marked Vs - a voltage source or a Voltmeter? Are V1 and V2 meters? What about the diamond with an arrow?
  4. Sep 27, 2009 #3
    Well that's all the question showed but I am certain that the circle marked Vs is a independent voltage source and the diamond with an arrow is a dependent source (voltage-controlled) and I think the squares are a circuit terminal elements I don't think it is important what they are just what way the current goes through them (like through the positive or negative side first to determine + or - current.
  5. Sep 27, 2009 #4


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    Very strange - I've never seen anything like it before.
    Anyway, it says V2 = 1000*i2 and i2 = 5, so V2 = 5000.
    V2 is supplied by the 5V1, so we have 5V1 = 5000 and V1 = 1000 Volts.
    V1 is the connected across Vs, so Vs = V1 = 1000 Volts.
  6. Sep 27, 2009 #5
    Ok. Would it matter if i2 is in mA not A or would that not effect it?
  7. Sep 27, 2009 #6


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    Homework Helper

    Good catch! Change my 5 to .005.
  8. Sep 27, 2009 #7
    Ok thanks for the help.
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