# Electronics Basics

##### by Waqar Ul Hasan - ( 11-10-2016 )

Power & Electronics Fundamentls - How does it Work ?

#### Magnetism :

As we know that If we have a magnate. It will stand still in "North" and "South" direction. And it will have a magnetic field. Which is stronger on the magnets poles. As we also know that if we put two magnates together they will attract each other or repel each other. As a fundamental law of Magnetism.

Direction Behavior Direction
N ( North ) Repel N ( North )
S ( South ) Repel S ( South )
S Attracts N
N Attracts S

and vise versa.

So this basic law or behaviour has many applications in our daily life. By converting Electricity in to Mechanical Energy. As in the case of Motors we use on a Multi-Rotor. So, lets apply the Law of Magnetism to Electricity under a Micro, Nano, Pico , .... or a Google-Scope 😉 , means (10 raise to power -100) – Scope 😉

#### Electricity :

Describing Electricity in its simplest form, we can say that electricity is the flow of electrons. To understand this behaviour properly we must look at the Atom and its components. Which in return give us the same behaviour as we have seen in Law of Magnetism.

An Atom has Protons (+ Positive) and Neutrons (neutral) in its Nucleus and Electrons (-Negative) that rotate around the nucleus in different orbits or shells. The electron in the outer most shell of an Atom called "Valence" electrons. As the Protons have plus charge and Electrons have negative charge. So the electrons get pulled to the nucleus due to the force of attraction and stays in their shell due to the "Centric Fugal Force." Because the Electron moves so fast and completes one rotation in a 1 Attosecond.

1 Attosecond = 10 raise to power -18

If an atom have the same number of Protons and Electrons, Its called a "Neutral" Atom. If an atom has more Protons than Electrons. Such an unbalanced Atom has a Positive charge due to the more number of Protons than Electrons. So, its called a "Positive Ion". Vice verse, If an Atom has more Electrons than Protons than its called a "Negative Ion", due to the more negative charge.

A part from the bound electrons to their shells. An Atom can have some "Free Electrons". That can move from one atom to the next quite easily. Also they move easily in "Conductors" than non-Conductors or "Insulators". Like metals and so on. Free Electrons can be produced by distributing the natural balance between Electrons and Protons. While applying the energy, heat, friction or a chemical reaction. By doing so Electrons in the outer most shell will gain more energy and leave their shell and become the negatively charged Free Electrons.

For instance in a Battery we have positive and negative poles. If we then physically separate the positive and negative ions by a chemical reaction. This will give us a charged battery. And if we then attach the battery in a Path or Circuit with a motor's positive and negative terminals. Then the Free Electrons will start to flow from battery's Negative to Positive Terminals.

So this is the flow of Electrons that is called "Current" and is mentioned with the latter "I". We can then measure the Magnitude of the Current. That the number of Electrons passed by in a specific amount of time in a Conductor. The current is measured in Ampere or "Amps". So for the sake of our ESCs or Flight Controller circuits; The current is passed in a very small amount. That's why we measure in Milli-Amps or "mA".

So just for the idea, In order to create one Milliampere current we need the following number of electrons.

1mA = 6,250,000,000,000,000 Electrons.

The flow of electrons in a Circuit also produce the Electromotive Force or Pressure. This force or Pressure also known as Potential and measured in Voltage, mentioned with the latter E.

#### Basics of Power :

Symbole Units - Explanation
V Volts Voltage Pressure
I ( E ) Amps Current Amount of Electricity flowing in a Circuit / Volume
W Watts Power Work that can be done
Ohms Resistance Resistance

Watts = Volts x Amps OR Power = Voltage x Current OR W = V x i

AC Voltage Ṽ & DC Voltage
AC Current Ã & DC Current

#### Ohm's Law :

Current is directly proportional to voltage and inversely proportional to resistance.
Current = Voltage / Resistance
(E) I = V / R
or
V = I . R

#### In Case of Directly Proportional :

As the equation shows by increasing the Voltage and keeping the Resistance constant the current is going to increase.
OR
If we increase the Resistance the Current will Decrease and If we decrease the Resistance the Current will Increase.

#### In Case of Inversely Proportional :

And if you increase the Resistance and keep the Voltage same the Current will decrease.
-> Current flows differently in different type of Materials and Conductors.

#### Resister :

A Resister blocks or impede the flow of Electricity.

#### Capacitor :

keywords : Electronics, Multimeter, Electronics Components, Magnetism, Motors, Battery