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Homework Help: A circuit analysis problem

  1. Oct 8, 2005 #1
    PROBLEM:the current at the terminals of a certain current source is measured with an ammeter having an internal resistance [tex]R_i=10 ohms[/tex] and is found to be [tex]11.988 mA[/tex] ;adding a [tex]1.2 kilo -ohms[/tex] resistance between the source terminals causes the ammeter reading to drop to [tex]11.889 mA[/tex].Find [tex]i_s[/tex] and [tex]R_s[/tex]

    NOTE:[tex]i_s[/tex] and [tex]R_s[/tex] constitute a practical current source.i.e [tex]R_s[/tex] is the internalresistance of the source [tex]i_s[/tex]
     
  2. jcsd
  3. Jul 6, 2017 #2

    scottdave

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    For a practical current source, the internal resistance should be shown as a resistor parallel to the "ideal" current source.
     
  4. Jul 6, 2017 #3

    berkeman

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    Misplaced homework thread closed for Moderation...
     
  5. Jul 6, 2017 #4

    berkeman

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    Oh duh, this is a way old problem that got put in the Open Practice Problems forum. Dave, I don't think the OP is going to read our replies...
     
  6. Jul 7, 2017 #5

    scottdave

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    Ha, I just realized what the date was on that.
     
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