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Homework Help: Concept question: Current

  1. Mar 31, 2010 #1
    1. The problem statement, all variables and given/known data

    Hi. This isn't exactly a homework question but a concept question. So when resistors are connected in series, I know that I total= I1=I2=I3...etc.....

    but if the resistors are different i don't understand how the current can be the same, even if they are in series...

    like, if you have a 2R resistor and a 9R resistor, connected in series, why would the current through each resistor be the same? Why wouldnt the current be less for the 9R resistor??? I thought greater resistance meant less current!!!

    i just DON'T understand!!!!

    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Mar 31, 2010 #2
    Tell me, if you turn on the water to your hose and let it all flow out, how much water is flowing out then compared to if you put a little kink in it? Think about it a little, and after that listen to what I have to say. The answer is that is, of course, the same amount of water comes out in both cases. When the water goes through that little kink there might be a little more power in the water because it is forced to go through such a small space, too much of a kink and the hose might even burst. In the end, however, the same amount of water that was there before the kink has to still be there after. Where would it go otherwise? It's the same with the resistors connected in series. Instead of a flow of water, you have a flow of electrons. The electrons might prefer to go through the 2R resistor than the 9R resistor, but they really don't have any choice because they have to go through both regardless.
     
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