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Homework Help: Equilvalent Resistance Problems

  1. Feb 1, 2004 #1
    How do you figure out the equilvalent resistance of a complex- circuit?

    How does one figure out potential difference of a complex-circuit?
  2. jcsd
  3. Feb 2, 2004 #2
    There are various Theorems including symmetry principles to solve the Complex Pros. etc. For eg Kirchoff's Law etc.

    Pls give us an Ex where u want to apply these Th or the circuits which u find complex
  4. Feb 3, 2004 #3

    Problem 21.
    A(n) 8.8 ohm resistor with a(n) 4.4 ohm resistor are connected inseries with a battery. The potential difference across the 4.4 ohm resistor is measured as 9 V.
    Find the potential difference acrosss the battery. In V.
    Note: I don't know where to start?

    Problem 22.
    A(n) 9.2 ohm resistor a(n) 4.4 ohm resistor are connected in series to a battery, and the current through the 9.2 ohm resistor is 1.3 A.
    Find the potential difference across the battery. In V.
    Note: How do i start?

    Problem 24.
    A. A 26.6 ohm resistor is connected in parallel to a 13.5 ohm resistor. These are joined in series to a 8.30 ohm resistor and a source with a potenital difference of 37.0V.
    Calculate the equivalent resistance. In units of ohms.
    Note: I don't know where to start.

    C. Calculate the current in the first resistor. Answer in A.

    E. Calculate the potential difference across the first resistor. Answer in units of V.
  5. Feb 4, 2004 #4
    These are probably simpe problems just dealing with ohms law.

    You first need to understand the ohms law and application in simple series and parallel circuits
  6. Feb 5, 2004 #5


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    Staff Emeritus
    Science Advisor
    Gold Member

    For the first 2 remember that current in a series circiut is constant throught all elements.

    In the first problem you are given voltage and resistance, use ohms law to find the current. Then use that current to find the voltage across the other resister. Now add the voltages to get the battery voltage.

    The second problem is very similar, think about it.

    For the third problem you need to now how to combine individual resistors to get a total resistance. RTFM. Once you have total resistance you have total current. Should be stright forward from there.
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