Electronics Handbook/Electricity

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Electrostatic refers to the process of matter becomes Electric Charge

Normally all matter are neutral or have net Charge equal to zero . When an object loses electron it becomes Positive Charge . When an object gains an electron it becomes Negative Charge

Matter + e --> [-]
Matter - e --> [+]

Electric Charge

All Electric Charges pocess a Quantity of Electric Charge called Electric Charge denoted as Q measured in Couloum (C) .

Positive Charge, +Q
Negative Charge, -Q

Electric Field

Electric Field is defined as Electric Field Lines radiate outward for Positive Charge or inward for Negative Charge. Electric Field is denoted as E measured in N/C .

Negative Charge , E . ---> Negative Charge <--- .
Positive Charge , E . <--- Positive Charge --->

Magnetic Field

Magnetic Field is defined as Elliptical Magnetic Field Lines rotates in clockwise direction for Negative Charge and Counter-Clockwise for Positive Charge

Negative Charge , B .
Positive Charge , B .

Interaction between Charges

Charges interact with each other according to Coulomb's Law and creating Electric Force between Charges as follow

Like Charges repulse . Unlike Charges attract , Negative Charge attract Positive Charge .
When different charges interact with each other example Nagative Charge attracts Positive Chrages creates Kinetic Energy in Electricity.
F = k \frac{Q_+ Q_-}{r^2}
When there is a difference in Charge's Quantities that creates Potential Difference in Electricity
mQ - nQ = (m-n) Q


ElectroMotive Force

If there is a Electromotive Force that sets stationary charge to move in straight motion to cause a flow of charges called Current then the Electric Field can be calculated by Ampere's Law as follow

F = E Q
E = \frac{F}{Q}
I = \frac{Q}{t}

ElectroMagnetoMotive Force

If there is a ElectroMagnetomotive Force that can change the direction of the moving charge perpendicular to the initial direction of moving charge such that Positive charge will moved up perpendicular to the initial direction and Negative Charge will move down perpendicular to the initial direction then Magnetic Field can be calculated by Lorenzt's Law

F = \pm B v Q
B = \frac{F}{v Q}

ElectroMagnetic Force

ElectroMagnetic Force is the total force acting on the moving charge equals to the sum of the Electromotive Force calculated by Ampere's Law plus the Magnetomotive Force calculated by Lorentz's Law.

F = E Q \pm B v Q = Q ( E \pm v B )

Matter and Electricity

Band gap comparison.svg

Matter that interact with Electricity is divided into three groups Conductor,Non Conductor,Semi Conductor depends on the ease of how current flow in the matter


All matter that allows current to flow with ease are called Conductor. For example all Metals like Zinc (Zn), Copper (Cu) are used to make Conductor

Non Conductor

All matter that does not allow current to flow in it are called Non Conductor . For example Rubber

Semi Conductor

All matter that allows current to flow somewhere between conductor and non conductor are called Semi Conductor . For example Silicon (Si), Gemanium (Ge)