ECED 2000 – Electric Circuits
Chapter 1.3 - Circuit Variables
Electric charge
• Bipolar
• Exists in discrete quantities
• Separation of charge / charges in motion => electrical effects
Voltage
Current
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ECED 2000 – Electric Circuits
Current, voltage, power, and energy review
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ECED 2000 – Electric Circuits
Chapter 1.4 – The Ideal Basic Circuit Element
1. It has only two terminals;
2. It is described mathematically in terms of
current and/or voltage;
3. It cannot be subdivided into other elements.
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ECED 2000 – Electric Circuits
Chapter 1.5 – Power and Energy
Power is the rate at which energy is absorbed or supplied.
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ECED 2000 – Electric Circuits
Chapter 1.5 – Power and Energy (cont’d)
Example:
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ECED 2000 – Electric Circuits
(a) an ideal independent voltage source
(b) an ideal independent current source.
(a)an ideal dependent voltage-controlled voltage source,
(b)an ideal dependent current-controlled voltage source,
(c) an ideal dependent voltage-controlled current source,
(d)an ideal dependent current-controlled current source.
Chapter 2. voltage and current sources
Examples
Example 2.1 Testing
Interconnections of Ideal Sources
(a)
(b)
(c)
(d)
(e)
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Examples
Example 2.2 Testing
Interconnections of Ideal Sources
(a)
(b)
(c)
(d)
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ECED 2000 – Electric Circuits
Chapter 2.2 – Electrical Resistance (Ohm’s Law)
Resistor –
Ohm’s law
Resistance:
R=
unit: ohm (Ω)
Conductance:
G=1/R
unit: siemens (S)
or mho
Power in a resistor:
p=
p=
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ECED 2000 – Electric Circuits
Chapter 2.2 – Resistor
Black
Brown
Red
Orange
Yellow
Green
Blue
Violet
Grey
White
0
1
2
3
4
5
6
7
8
9
•
•
•
•
•
First find the tolerance band, it will typically be gold ( 5%) and
sometimes silver (10%).
Starting from the other end, identify the first band - write down
the number associated with that color; in this case Blue is 6.
Now 'read' the next color, here it is red so write down a '2' next
to the six. (you should have '62' so far.)
Now read the third or 'multiplier exponent' band and write down
that as the number of zeros.
In this example it is two so we get '6200' or '6,200'. If the
'multiplier exponent' band is Black (for zero) don't write any
zeros down.
Taken from http://wiki.xtronics.com/index.php/Resistor_Codes
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ECED 2000 – Electric Circuits
Chapter 2.2 – Resistor
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Figure 2.8 The circuits for Example 2.3.
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ECED 2000 – Electric Circuits
Chapter 2.3 – Construction of a Circuit Model
Ex 2.5
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ECED 2000 – Electric Circuits
Chapter 2.3 – Construction of a Circuit Model
Ex 2.5
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ECED 2000 – Electric Circuits
Chapter 2.4 – Kirchhoff’s Laws
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ECED 2000 – Electric Circuits
Chapter 2.4 – Kirchhoff’s Laws
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ECED 2000 – Electric Circuits
Chapter 2.4 – Ohm’s Law & Kirchhoff’s Laws
Ex 2.8
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AP 2.5 p.42
AP 2.6 p.42
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