1. Electric Circuits I (EELE 2310)

2. Electric Power Engineering site.iugaza.edu.ps/ajasser
Assad Abu-Jasser, PhD
Electric Power Engineering
site.iugaza.edu.ps/ajasser

3. Chapter One
Circuit Variables

4. Circuit Theory Electric Circuit
Mathematical model that approximates the behavior of an actual electrical system
Commonly used to refer to an actual electrical system as well as to the model that represents it

5. Problem Solving Identify what’s given and what’s to be found
Sketch a circuit diagram or other visual model
Think of several solution methods and choose one
Calculate a solution
Use your creativity
Test your solution

6. The SI Units Quantity Basic Unit Symbol Length meter m Mass kilogramKg
Time
second S
Electric Current
ampere A
Temperature
degree kelvin oK
Luminous intensity
candela cd

7. Circuit Analysis An Overview
Need
Design Specifications
Concept
Circuit Model
Ideal Circuit Components
Circuit Analysis
Physical Prototype

8. Voltage and Current
The concept of Electric Charge is the basis for understanding all electrical phenomena
The electrical effects caused by charges in motion depend on the rate of charge flow. Electric Current is the rate of charge flow.
Separation of charges expends energy. Voltage is the energy per unit charge created by the separation of charges.
The Charge is bipolar (+ve & -ve)
Electric Charge exists in discrete quantities (1.6022×10-19 C)
Electrical Effects attributed to separation of charges and charges in motion

9. The Ideal Basic Circuit Element
Two terminals
It is described mathematically
It can not be subdivided

10. Passive Sign Convention
Whenever the reference direction for the current in an element is in the direction of the reference voltage drop across the element use a positive sign in any expression that relates the voltage to the current. Otherwise, use a negative sign.

11. Power and Energy Definition and Equation
Power: time rate of expending or absorbing energy

12. Power and Energy Working Example
i=4 A and ʋ=-10 V

13. End of Chapter One