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Fundamental Physics/Electromagnetism

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

Contents

Introductory MaterialEdit

ElectrostaticsEdit

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

 


MagnetostaticsEdit

 
 
 
 
 
 
 
 

ElectromagnetismEdit

ElectromagnetEdit

 
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
 

 
 
 
 

ElectromagnetizationEdit

 

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

  Electromagnet
 
 
 
 
Electromagnetic induction
 
 
Electromagnetic oscillation


 
 
 
 
 

  Electromagnetic wave


Electromagnetic wave equation
 
 

Electromagnetic wave function
 
 
 
 

≈≈≈ Electromagnetic wave radiation
 


 
 
 
 

ResourcesEdit