Electronics a layman’s Introduction
Part 1 | Part 2 | Part 3 | Part 4
If you are anything like me, you have at one point held your mobile phone, laptop, camera or even just watch in your hand and wondered?
How does this little gadget actually do it’s job?
How does it know what I want?
Or when I want it?
Or how to reply to me?
Well if these and more curiosities have come up as you have interacted with various gadgets, then you are at the right place!
When you unlock your phone’s screen you are connecting a source of electricity your phone’s battery to an LED screen in a conductive path.
This path is more formally known as an electric circuit.
Now while unlocking your phone’s screen is a pretty contrived and an overly simplified example it does open the door to imagining how much can be achieved using the power of electricity in systems known as electrical systems.
Electrical systems use what is known as an electric current to perform all sorts of tasks. In order to understand all this mumbo jumbo we need to understand what electricity is and how it powers things like screens.
What is Electricity?
Electricity is a set of physical phenomena associated with the presence of electrons that contain an electrical charge and their motion.
This motion of electrically charged electrons is referred to as an Electric Current.
Electrical charge is kind of a force found within particles known as atoms which are the building blocks to everything you see and feel around you. There are two different forces usually exhibited these within atoms the two forces are known as positive and negative charges.
Under normal circumstances, atoms have the same amount of negative and positive forces and atoms in this states are said to be electrically neutral.
The force that keeps an atom’s particles together is known as an electromagnetic force
Conductors and Insulators
Some substances such as air and plastic have tight bounds with their electrons and hence the electrons don’t move around as much, substances with this quality are known as Insulators.
Other substances such as the metal copper have free electrons wandering between atoms usually moving at random, when these electrons are shoved they all tend to move in one direction and because even the electrons at the ends move all at once the motion appears instantaneous, substances with this quality are known as Conductors.
Getting Electricity
We achieve the phenomena of electricity through giving a charge to electrons in a conductor, conductors enable us to move current since applying some force to the electrons generally gets them to move in the direction we intend.
Hence when we flip a switch the light goes on, almost instantly.
We can tap into electricity in order to do interesting things with it, for example make a filament glow, rotate a motor shaft, even vibrate speakers to make recognisable sounds and sometimes indeed even enjoyable ( we call this music). In order to do this, we let an electric current flow from a source to a place where it can do something useful in a circuit
In order to get electrons flowing, we need to apply a force, this force is known as voltage and measured in units called volts. Voltage kind of works like pressure in water, the higher the pressure the more powerful the push and so it follows that the higher the voltage the higher current that is pushed through a conductor.
Circuits
As we learned earlier electric currents don’t just flow anywhere i.e they flow in conductors and not in insulators.
Electrons only keep flowing if you provide a closed conductive path as known as an electrical circuit. Conductors such as copper are usually formed into a wire that is used to let us transfer electricity.
If a break exists in the conductive path the electrons get stuck at the dead end.
Circuits need at least 3 things in order for electrons get energised and deliver their energy to something that needs work done
- A source of electricity to provide the force that nudges the electrons (voltage)
- A load, a thing that uses electrical power to do something
- A path, a conductive path to channel the electric current between the source and the load
Is all this worth the Work?
In electricity, work is defined as a measure of energy that a device uses over a certain amount of time.
The total energy used in doing work over some period of tome is known as power and is measured in watts, we can calculate it as follows
power = voltage * current
Electronics is all about using specialized devices known as electronic components e.g resistors, capacitors, inductors and transistors to control electric current in such a way that it performs a specific function e.g
- Buzzing your phone
- Lighting a bulb
- Running motors
- Computing logical equations
In what interesting ways would you use electricity?
Next time we cover how to manipulate electricity to make exciting things happen!
Wanna join a community of makers learning and improving together? Join us on the #electronics-iot channel on our Discord Server
Originally published on the Little Kidogo blog at https://blog.littlekidogo.co.za/electronics-intro/
Back to soldering 😛
