Circuits with Resistor Combinations (2.6, 7.7)

1
Circuits with Resistor Combinations (2.6, 7.7)

• Prof. Phillips
• Jan 31, 2003

2
Solving Circuits with Series and Parallel
Combinations

• The combination of series and parallel impedances
  can be used to find voltages and currents in
  circuits.
• This process can often yield the fastest
  solutions to networks.
• This process may not apply to complicated
  networks.

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Series and Parallel Impedances

• Impedances are combined to create a simple
  circuit (usually one source and one impedance),
  from which a voltage or current can be found
• Once the voltage or current is found, KCL and KVL
  are used to work back through the network to find
  voltages and currents.

4
Example Resistor Ladder
1kW
1kW
1kW

1kW
10V
2kW
2kW

• Find V1, V2, and V3

5
Example Resistor Ladder
1kW
1kW
1kW

1kW
10V
2kW
2kW

• Find an equivalent resistance for the network
  with V1 across it, then find V1 using a voltage
  divider.

6
Example Resistor Ladder
1kW

1kW
10V
7
Example Resistor Ladder
1kW
1kW
1kW

1kW
10V
2kW
2kW

• Find an equivalent resistance for the network
  with V2 across it, then find V2.

8
Example Resistor Ladder
1kW
1kW

10V
1kW
2kW
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Example Resistor Ladder
1kW
1kW
1kW

1kW
10V
2kW
2kW
10
Class Examples