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Current in a series circuit

  1. May 17, 2008 #1
    why is current SAME in a series circuit ? i know it's one path, so what if there's one path? can you please answer with a visual and helpful explanation ? i dont understand this concept. i want to know why does it stay the same in the whole circuit ?
  2. jcsd
  3. May 17, 2008 #2
    A series path can be comprised of multiple resistors. Total resistance of the path would be the sum of all resistances. If you apply voltage between the beginning and end of the path, a current will start flowing according to Ohm's law.

    [tex] i = \frac {V}{R} [/tex]

    So basically series resistance behaves like a one big resistor.
  4. May 17, 2008 #3


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    This is one of those situations where the annalogy between electrical current and water flow can prove usefull. Suppose you poor water into one end of a hose. If you poor in 5 gal./min. at one end, then 5 gallons per minute will have to come out the other end. If you put a restriction somewhere in the hose, you'll need to apply more pressure at the one end in order to get those same 5 gallons per minute to flow in. If you place several more restrictions, you'll increase the amount of pressure needed. If the additional pressure is not applied, the rate of flow will slow down, but the amount of water flowing in one end will always be the same as the amount flowing out the other end, because there is "only one path"; nowhere else for the flow to go.
    Last edited: May 17, 2008
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