Value of Resistor in Circuit

Discussion in 'Homework Help' started by electronic_engineer, Aug 10, 2016.

  1. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    What Value of R should be used in Figure if it is required that the voltage across R be 36V?
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  2. Jony130

    AAC Fanatic!

    Feb 17, 2009
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    But first you need to show us your attempt.
     
  3. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    As the voltage across R is needed to be 36V , similar will be voltage across 6KOHM resistor, so 6m Amp would be current through it,

    If I know about the total current drawn from voltage source , I can, then, know the current through R resistor by current division principle, but I dont know the total current. Or if I know the value of R then combining R in parallel with 6K ohm resistor and then adding the equivalent with 2Kohm and 4Kohm, in this way I can get the current drawn from voltage source, but value of R is required and total current provided by voltage source is not given, how can I solve now?
     
  4. Jony130

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    But you know the voltage drop across 2kΩ resistor and 4kΩ resistor. Is this information not enough ?
     
  5. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    How can I know the voltage drop across 2Kohm resistor and 4Kohm resistor?

    I only know that voltage drop across both will be 90-36 V, but what will be voltage across each 2Kohm and 4Kohm individually? How can I know that when I don't know the current through them?
     
  6. Jony130

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    But 2kΩ and 4kΩ resistor are connected in series. So you know the current, right?
     
  7. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    They are in series but 6Kohm resistor in parallel with R ohm is also in series with them when I dont know the value of R , how can I calculate current?
     
  8. Jony130

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    Do you know that in series circuit we have the same current ? Also we already know the voltage drops across 2kΩ and 4kΩ resistors.
    So we can find total current.
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  9. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    Yeah , now I got it , thank you so much :) really I made such an stupid mistake
     
    Last edited: Aug 10, 2016
  10. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    I got right answer :) :)
     
  11. Jony130

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    I'm glad that I could help.
     
  12. DGElder

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    Apr 3, 2016
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    Don't blame it on your parents.
     
  13. electronic_engineer

    Thread Starter New Member

    Aug 2, 2016
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    Typing error in excitement
     
    Jony130 likes this.
  14. DGElder

    Member

    Apr 3, 2016
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    Yes I got that ;)
     
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