![• Electric charge is a fundamental property of matter.
• Charge exist only in positive or negative integral multiple of electronic
charge, -e, e= 1.60 × 10-19 coulombs. [It may be noted here that in 1962,
Murray Gell-Mann hypothesized Quarks as the basic building blocks of
matters.
• Quarks were predicted to carry a fraction of electronic charge and the
existence of Quarks have been experimentally verified.]
• Principle of conservation of charge states that the total charge (algebraic
sum of positive and negative charges) of an isolated system remains
unchanged, though the charges may redistribute under the influence of
electric field.
• Kirchhoff's Current Law (KCL) is an assertion of the conservative property
of charges under the implicit assumption that there is no accumulation of
charge at the junction.](https://image.slidesharecdn.com/lecture-2introduction-230124190455-26389a3f/85/Lecture-2-Introduction-pptx-4-320.jpg)
![Vector Analysis:
• The quantities that we deal in electromagnetic theory may be
either scalar or vectors [There are other class of physical quantities
called Tensors: where magnitude and direction vary with co ordinate axes].
• Scalars are quantities characterized by magnitude only and algebraic sign. A
quantity that has direction as well as magnitude is called a vector. Both scalar
and vector quantities are function of time and position .
• A field is a function that specifies a particular quantity everywhere in a region.
Depending upon the nature of the quantity under consideration, the field may be
a vector or a scalar field.
• Example of scalar field is the electric potential in a region while electric or
magnetic fields at any point is the example of vector field.](https://image.slidesharecdn.com/lecture-2introduction-230124190455-26389a3f/85/Lecture-2-Introduction-pptx-6-320.jpg)
Lecture-2 (Introduction).pptx
- 1. Introduction
- 2. Mathematical Fundamentals Introduction : Electromagnetic theory is a discipline concerned with the study of charges at rest and in motion. Electromagnetic principles are fundamental to the study of electrical engineering and physics. Electromagnetic theory is also indispensable to the understanding, analysis and design of various electrical, electromechanical and electronic systems. Some of the branches of study where electromagnetic principles find application are: RF communication Microwave Engineering Antennas Electrical Machines Satellite Communication Atomic and nuclear research Radar Technology Remote sensing EMI / EMC (Electromagnetic Compatibility) Quantum Electronics VLSI
- 3. • Electromagnetic theory is a prerequisite for a wide spectrum of studies in the field of Electrical Sciences and Physics. • Electromagnetic theory can be thought of as generalization of circuit theory. • There are certain situations that can be handled exclusively in terms of field theory. In electromagnetic theory, the quantities involved can be categorized as source quantities and field quantities. • Source of electromagnetic field is electric charges: either at rest or in motion. However an electromagnetic field may cause a redistribution of charges that in turn change the field and hence the separation of cause and effect is not always visible.
- 4. • Electric charge is a fundamental property of matter. • Charge exist only in positive or negative integral multiple of electronic charge, -e, e= 1.60 × 10-19 coulombs. [It may be noted here that in 1962, Murray Gell-Mann hypothesized Quarks as the basic building blocks of matters. • Quarks were predicted to carry a fraction of electronic charge and the existence of Quarks have been experimentally verified.] • Principle of conservation of charge states that the total charge (algebraic sum of positive and negative charges) of an isolated system remains unchanged, though the charges may redistribute under the influence of electric field. • Kirchhoff's Current Law (KCL) is an assertion of the conservative property of charges under the implicit assumption that there is no accumulation of charge at the junction.
- 5. • Electromagnetic theory deals directly with the electric and magnetic field vectors where as circuit theory deals with the voltages and currents. • Voltages and currents are integrated effects of electric and magnetic fields respectively. • Electromagnetic field problems involve three space variables along with the time variable and hence the solution tends to become correspondingly complex. Vector analysis is a mathematical tool with which electromagnetic concepts are more conveniently expressed and best comprehended. • Since use of vector analysis in the study of electromagnetic field theory results in real economy of time and thought, we first introduce the concept of vector analysis.
- 6. Vector Analysis: • The quantities that we deal in electromagnetic theory may be either scalar or vectors [There are other class of physical quantities called Tensors: where magnitude and direction vary with co ordinate axes]. • Scalars are quantities characterized by magnitude only and algebraic sign. A quantity that has direction as well as magnitude is called a vector. Both scalar and vector quantities are function of time and position . • A field is a function that specifies a particular quantity everywhere in a region. Depending upon the nature of the quantity under consideration, the field may be a vector or a scalar field. • Example of scalar field is the electric potential in a region while electric or magnetic fields at any point is the example of vector field.
- 7. Figure 1 (a) Unit vectors ax, ay, and az, (b) components of A along ax, a^,, and az.
- 8. Figure 2 Illustration of position vector rP 3a, + 4a., + 5az.
- 9. Figure 3 Direction of A X B and an using (a) right-hand rule, (b) right-handed screw rule.