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Discussion in 'General Electronics Chat' started by aftab0379, Jan 11, 2015.

mmy question is if resistor opposes current then why current before the resistor and after resistor

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  1. aftab0379

    Thread Starter New Member

    Jan 11, 2015
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    mmy question is if resistor opposes current then why current before the resistor and after resistor same although it opposes current...iam very confuse someone plz answer
     
  2. #12

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    Nov 30, 2010
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    Before you install the resistor it does not oppose the flow of current. After you install the resistor is does oppose the flow of current. Therefore, the current is NOT the same before and after you install a resistor.

    If a garden hose opposes the flow of water, why is the flow of water the same at both ends of the hose? Because water and current do not disappear in the middle of a resistance to flow.
     
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  3. aftab0379

    Thread Starter New Member

    Jan 11, 2015
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    Thanks bro
     
  4. atferrari

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    Creating a poll on this, makes no sense
     
  5. MaxHeadRoom

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    Jul 18, 2013
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    I guess #12 votes 12? :p
    Max.
     
  6. #12

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    The only way I ever won an election: run unopposed. :(
     
  7. tracecom

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    Apr 16, 2010
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    I just voted for you; send pork.
     
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  8. spinnaker

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    Oct 29, 2009
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    Everyone knows the answer is 42 but it was not added as an option. :)
     
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  9. joeyd999

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    I don't like the terminology "a resistor opposes current." It literally is not correct. Kinda like the old, incorrect, adage "current takes path of least resistance."

    If I've got a 1A current source across a 1 ohm resistor, is the resistance opposing the current? Seems if that were so, I'd see a drop in current which, of course, doesn't happen.
     
  10. #12

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    Semantics. Please don't pee in the soup. The beginner is having enough difficulty.
     
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  11. joeyd999

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    In fact, it would be technically more accurate, though still incorrect, to say that "resistance opposes voltage".

    A resistance applied in parallel with a voltage source develops exactly an equivalent, and opposing voltage across its terminals.
     
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  12. joeyd999

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    When I train young dogs, I try not to develop bad habits in them that I'll have to break later.

    It's easier to teach slow and correctly when they're young than to have to fix problems when they are older.
     
  13. toffee_pie

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    Oct 31, 2009
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    Assuming voltage stays the same then an increased current will return a drop in resistance and vice verse, this pretty clearly shows that resistance is central to the flow of current itself.
     
  14. #12

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  15. WBahn

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    Mar 31, 2012
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    How will increasing the current cause the resistance to drop? If the voltage is staying the same, how will you increase current in the first place?
     
  16. aftab0379

    Thread Starter New Member

    Jan 11, 2015
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    Yes bro iam beginner to engg thats why iam confuse
     
  17. wayneh

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    Sep 9, 2010
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    A resistor opposes current in the same way that a water valve opposes water flow. It's a restriction. More power (voltage or pressure) must be supplied at the source to maintain the same flow at the output, with the excess power being dissipated at the restriction. If more power is not supplied, the flow decreases.

    Just as with water, the flow on either side of the restriction is identical. No extra water mass or electrical charge is added or removed, only energy.
     
  18. joeyd999

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    I like the word "restricts" better than "opposes". "Opposes" implies "equal and opposite". And "oppose" is not a synonym for "restrict".
     
  19. wayneh

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    Agreed. It may just be semantics but I can see how "oppose" might imply the active use of outside force or energy, as opposed to a passive consumption of energy.
     
  20. toffee_pie

    Active Member

    Oct 31, 2009
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    this is the way these things go, look at batteries, lithiums. The lower the internal resistance........what happens?

    yes, the higher the current it can discharge, and the voltage will still be at the nominal level, 3.7v or whatever.

    This equates to ohms law, and my original point.
     
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