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VOLTAGE SOURCE

Independent Voltage Source

Dependent Voltage Source

Voltage-controlled Voltage Source (VCVS)

Current-controlled Voltage Source

1

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CURRENT SOURCE

2

Independent Current Source

Dependent Current Source

Voltage-controlled current source (VCCS)

Current-controlled current source (CCCS)

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NETWORK TOPOLOGY

3

Branch:

A branch is a single element, e.g. resistor, voltage source.

Node:A node is the point of connection between 2 or more

branches.

Loop:A loop is any closed path in a circuit.

Fundamental Theorem of Network Topology:

b = l + n 1

b: branches

n: nodes

l: independent loops

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Series Connection

Same current through all resistors

If all resistors have the same value R, it is:

In general:

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Example: Voltage divider

2

1 2

0

2

1 2

} 21 2:

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Potentiometer

Symbol:

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Parallel Connection

1

1

Same voltage across all resistors

If all resistors have the same value R, it is:

1

In general:

.

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Reference: Lee, R. C, Dougherty, W., Electrical Injury:,

IEEE Trans. Dielectrics and Electrical Insulation, Vol. 10,No. 5, 2003

EXERCISE HUMAN BODY

Presume you put one hand to both feet and

body is connected to a 230 V voltage source.

Calculate the current running through the bodyusing internal tissue resistances from figure.

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EXERCISE EQUIVALENT RESISTANCE

Find current I in the circuit shown in figure (Answer: 4A)