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Homework Help: Resistor problems

  1. Jan 3, 2005 #1
    Question 1: A group of n resistors each of resistance R, are connected in series. What is the total resistance?What is the total resistance if the resistors are connected in parallel?

    Questions 2: A series-parallel group of resistors each of resistance R, have n equal resistances in series, in each of N row in parallel. What is the total resistance?(express your answer for 1 and 2 in terms of n,N & R);
     
  2. jcsd
  3. Jan 3, 2005 #2
    I guess u are at the start of your electrical theory and just learnt Ohm's Law.

    Ok we will go slow. Start with the n Resistors in series problem.

    1> We have a circuit with n resistors each of resistance R connected in series. Lets say we connect a battery of voltage V to this circuit which drives a current I through the circuit.
    2> Can u find the voltage across each resistor?
    3> Once u are done with step 2, lets rip out all the resistance and replace it with a single equivalent resistor (lets call it Req).
    4> Again we have the same setup, a battery of voltage V driving current I through the circuit. What is the voltage across Req?
    5> What is the relationship between the voltages u found in step 2 and the voltage u found in step 4?
    6> Once u are finished with step5, the answer is immediately seen ... if not post your working and we will help u further.

    -- AI
     
    Last edited: Jan 3, 2005
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