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Kirchoff's 2nd Law : Sign taking method

  1. Oct 8, 2006 #1
    I know Kirchoff's 2nd law but when applying to an electrical circuit i am bit confused :confused: with taking correct signs for emf,product of resistor & currect etc.
    Anyone please help me to solve problems related with Kirchoff's 2nd law in an easy way.
  2. jcsd
  3. Oct 9, 2006 #2
    When considering the second law, think of the potential DIFFERENCE. In other words, when you go through a loop in a certain direction, and you encounter an emf or resistor, check whether the energy level is greater than or less than after that object.
    Eg. if the direction of current is the same as the direction of ur loop, and u encounter an emf, take +ve since energy is supplied by the emf. Likewise its a -ve sign for resistors since energy is supplied TO the resistor.:smile:
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