Electricity works through the movement of electrons in conductors like wires and cables. Atoms contain protons with a positive charge and electrons with a negative charge that orbit the nucleus. In conductors, some electrons are loosely bound and can flow freely. When a closed circuit is formed connecting a voltage source, such as a battery, the voltage pushes the electrons to flow in one direction. Electrical components like resistors can control or use this electron flow to perform tasks. Transformers can induce electron flow between two circuits to change voltage levels. Alternating current periodically changes direction while direct current flows one way.

1. How electricity works
How does electricity work. In this article we’ll be learning the basic concept
behind how electricity works according to classical theory. We’ll cover Atoms,
electrons, protons, neutrons then move onto the difference between conductors
and insulators, wires and cables, circuits, volts and voltage, currents and amps,
resistors, resistance and ohms, induction and inductors, transformers,
capacitors and finally the difference between AC and DC power. These are the
basics to grasp in order to understand how electricity works before moving onto
more advanced areas of electrical and electronic engineering.
The Atom
Atom, neutrons, proton and nucleus
Everything is made from Atoms, including you! Different materials have
different types of atoms. At the centre of an Atom is the Nucleus, this houses
two particles known as the Neutron and Proton. The Neutron has no electrical
charge but the Proton has a positive electrical charge.
Surrounding the Nucleus are different layers of orbital shells which act like flight
paths for another type of particle known as the electron. The electrons travel
long these paths much like satellites orbit around our planet, except that the
electrons travel at almost the speed of light.
The negative charge of the neutrons is attracted to the positive charge of the
Proton which keeps the electrons in orbit. Each orbital shell can hold a set
number of electrons. The number of Protons, Neutrons and Electrons an Atom
has tells us which material it is and the combination is unique for each material.

2. free electron atom
Atoms hold onto their electrons tightly but some materials will hold onto their
electrons more tightly than others. The outer most orbital shell is known as the
Valance shell and in this shell some materials will have loosely bound electrons
which can float to other Atoms.
Conductors and insulators
conductors and insulators
Materials which can pass electrons are known as “Conductors” meaning they
can conduct electricity. Most Metals are conductors. Atoms which do not have
free electrons are known as insulators, materials like glass and rubber are good
examples of this.
We can combine Conductors and Insulators together to safely use electricity.
This is is done by surrounding the conductor with an insulator, this allows
electrons to flow but it restricts where they can flow to. This is how a cables and
wires work.

3. Wires and Cables
free electrons with no current applied
If we look inside a slice of Copper cable we would see the free electrons of the
atoms move from one atom to another, however this occurs randomly in any
direction.
electrical current flow in circuit
If the slice of cable were then connected in a closed circuit to a source of power
such as a battery, then the voltage will force the free electrons to move and this
will cause them to all flow in the same direction, to try and get back to the
other terminal of the battery.

4. Circuits
open and closed electrical circuit
The term circuits refers to a route which the electrons can flow along to get
between the two terminals of the power source (Positive and Negative).
When a circuit is closed then electrons can flow from one terminal to the other.
When a circuit is open then there is a gap in the circuit so electrons can’t flow.
We can place electrical components in the path of the free electrons which flow
in a circuit. This will force the electrons to flow through the component and this
can be used to perform work such as generate light.

5. Volts and Voltage
what is voltage
Voltage is a pushing force of electrons in a circuit, much like pressure in water
pipe. The more pressure you have the more water can flow. The more voltage
you have the more electrons can flow.
what is a volt joule coulomb
A Volt is a Joule per Coulomb. A Joule is a measurement of energy or work. A
Coulomb is a group of flowing electrons.
A 9V battery can provide 9 Joules of energy, in the form of work or heat, per
group of electrons that flow from one terminal of the battery to the other. In
this case the electrons from one terminal of the battery, through the L.E.D bulb
and then into the other terminal of the battery. Therefore 9 Joules of light and
heat is produced by the bulb.
Current, Amperes and Amps

6. what is an electrical current, amp, ampere
Current is the flow of electrons. When a circuit is closed then a current of
electrons can flow and when a circuit is open then no current can flow. We can
measure the flow of electrons just like you can measure the flow of water
through a pipe.
To measure the flow of electrons we use the unit of Amperes or Amps for short.
1 Amp means 1 Coulomb per second and one coulomb equals
6,242,000,000,000,000,000 electrons per second. This is an extremely large
number which is why they are grouped together and called Amps.
Resistors and Resistance
what affects resistance to current in a cable wire

7. Resistance is a restriction to the flow of electrons in a circuit. Wires which carry
the current will naturally have some resistance. The longer the wire the greater
the resistance. The thicker the wire the less the resistance. The resistance to
the flow of electrons is different for each material, the temperature of the
material will also affect the level of resistance.
resistor in a led circuit
Electrical circuit use specially designed components known as resistors to
purposely restrict the flow of electrons. This is used to protect other electrical
components from receiving too much current and it can also be used to
generate light and heat such as in an incandescent light bulb.
Resistance occurs when electrons collide with atoms. The number of collisions
varies by material, some materials such as Iron will have a very high rate of
collisions whereas other materials such as copper has much fewer collisions.
When collisions occur the atoms generate heat and at a certain temperature the
material will then start to produce light as well as heat, which is how the
incandescent lamps work.

8. Inductors and induction
electrical induction
When a wire is wrapped in a coil, it will produce a magnetic field as the current
passes through it. The cable would naturally create the magnetic field, its just
intensified by the shape of the coil. By wrapping the wire in a coil, the magnetic
field becomes so strong that it starts to affect the electrons within the wire
We can increase the intensity of the magnetic field simply by wrapping the wire
around an iron core. We can increase the number of rotations within the coil
and we can also increase the amount of current passing through the circuit to
produce larger and stronger magnetic fields. This is how electromagnets work,
its also the basis of how induction motors work. Click here for more information
of the working principle of induction motors.

9. magnetic induction
When a magnetic field is passed across a coil of wire, it will induce a voltage
into the wire caused by an induced electromotive force which is pushing the
electrons in a certain direction. If the coil is connected to a circuit this will cause
a current to flow. This is the basis of how an AC generator works and the power
available in the plug sockets of your home was produced in a very similar way.
Transformer
how transformers work
Transformers are a combination of all the points we’ve covered so far in this
article. We can create two separate circuits and use a transformer to induce
current from one circuit into the other.
By generating an AC current in a closed circuit and passing this current trough a
coil, which is in close proximity to another coil in a separate closed circuit, we
can create a transformer and induce a current from the first (primary) circuit
into the second circuit.

10. Transformers can be used to increase or decrease the voltage between the
primary and secondary circuits simply by changing the number of coils on either
side.Capacitors
how capacitors work
Capacitors force positive and negative charges to separate across two plates,
when it is connected to a power supply. This causes a build up of stored
electrons within an electric field. When a power supply is cut or interrupted
these charges will then be released where they will then meet up and flow
again. This provides a power source by only very briefly (seconds) as it will only
last until the separated charges have met up again. This is slightly similar to a
battery except it can’t maintain a power supply for as long.
Capacitors are very common and can be found in pretty much every electrical
circuit.
AC and DC power
AC vs DC alternating current and direct current

11. There are two types of power in use which are Alternating Current (AC) and
Direct Current (DC)
Alternating current simply means the current flow backwards and forwards in a
circuit as the terminals are constantly reversed. This is a bit like the tide of the
sea, it goes in and out repeatedly. Alternating current is the most common type
of electrical power and this is the type of power available in the power sockets
of your home.
Direct Current simply means that the current flow directly in only one direction.
This is what’s provided from batteries and Photovoltaic panels etc. This is most
commonly used in portable electrical goods.
We can convert between AC and DC using inverters, this is how the AC power
from our household power sockets can be used to charge our mobile phones
which use DC power .
Thank concludes this article for the basics of how electricity works. Below is a
video tutorial on the subject with more information and animations.
Watch This How Electricity Works Video : https://uii.io/Electricitywork