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Fundamental Physics/Electromagnetism

It is necessary to revise the following mathematical concepts as they are used throughout this course:


Introductory MaterialEdit


Electric charge
Electric charge Charge process Charge quantity Electric field Magnetic field
Negative charge O + e -> - - Q -->E<-- B ↓
Positive charge O - e -> + + Q <--E--> B ↑
Electric charge interaction
Coulomb law . Like charges repel, different charges attract . Negative charge attracts positive charge . The force of attraction negative charge attracts positive charge is called Electrostatic force can be calculated by Coulomb law as follow
Ampere law . The force that sets electric charge in motion from stationary state is called Electromotive force can be calculated by Ampere law as follow
Lorentz law . When electric charge interacts with magnetic field of a magnet, the magnetic force of the magnet will make electric charge to move perpendicular to the initial moving direction . The positive charge will move up, the negative charge will move down . The force of magnetic field that sets electric charge to move perpendicular to the intial moving direction is called Electromagnetomotive force can be calculated as follow
The sum of 2 forces Electromotive force and Electromagnetomotive force creates Electromagnetic force

Electrostatic field

The force of attraction of 2 different charges


The electric field of the charge in motion


Electric Potential

The potential of the electric field






Configuration Magnetic Field Magnetic field intensity
For a straight line conductor
circular magnetic field surrounds a point charge along the straight line  
For a circular loop conductor
circular magnetic field surrounds a point charge along the circular loop  
For a coil of N circular loops conductor
lines of magnetic field runs from North pole (Positive polarity) to South pole (Negative polarity)  

Electromagnetic inductionEdit

Electromagnetic induction takes place in a circular loop and a coil of N circular loops . According to Faraday, change in magnetic field will produce electric potential

For a single circular loop    
Coil of N circular loops




The way a coil of N circular loops turn metal inside the loops into a electromagnet


Maxwell's equation

Electromagnetism of a straight line conductorEdit


Electromagnetism of a circular loop conductorEdit



Electromagnetism of a coil of N circular loopsEdit

Electromagnetic induction
Electromagnetic oscillation


  Electromagnetic wave

Electromagnetic wave equation

Electromagnetic wave function

≈≈≈ Electromagnetic wave radiation