EE 1270: Introduction to Electric Circuits

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EE 1270 Introduction to Electric Circuits
Lecture 2 Ohm's Law Chapter 2 Circuit Elements
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Voltage and Current Sources
An Ideal Current Source
An Ideal Voltage Source
An ideal voltage source will provide a constant
voltage across its terminals regardless of the
current flowing into those terminals
An ideal current source will provide a constant
current flowing through its terminals regardless
of the voltage across those terminals
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Voltage and Current Sources
____ Controlled Voltage Source
____ Controlled Voltage Source
____ Controlled Current Source
____ Controlled Current Source
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Example 2.1 Valid or Invalid?
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Example 2.2 Valid or Invalid?
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AP 2.1
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Ohm's Law
R Electrical Resistance O v Voltage V i
Current A
Resistance is created by the atoms in a material
through which the electrons are moving
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Example 2.4 Circuit Model of a Flashlight
Lamp
Metal Case
Coil Wire
Switch
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Example 2.5 Circuit Model of a Flashlight
Q What if the curve is nonlinear?