Lesson 01 – Basic Electricity
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Welcome to Electronics For Fun
Lesson 1 – Basic Electricity
As I introduce new terms, I have included a link to Wikipedia. Read ahead a little, and if you still need help you can click on any orange word below for more information than you probably want. 🙂
What is Electricity
Electricity is a source of power that we use to power everything like flashlights and remote controls, household lamps and appliances, and hugh electric motors that provide the power to move trains.
A very brief explaination would start with an atom which is made up of electrons spining around a nucleus of protons and neutrons. The electrons have a negative charge, the protons have a positive charge, and the neutrons have no charge. Everything we know of is made up of atoms, not just electrical things. Even a wooden desk is made of atoms as an example.
The image below shows the makeup of a single atom of Helium containing 2 negatively charged electrons shown in yellow, 2 positively charged protons shown in red, and 2 “neutral” neutrons shown in green.
Every atom is normally said to be electrically neutral. That is because they have the same number of negatively charged electrons as they do positively charged protons. Certain actions will cause some atoms to “lose” one or more electrons, making those atoms “positively charged”. Other nearby atoms will then “gain” those electrons and will have too many, making those atoms negatively charged.
That type of energy, called electricity, can either build up in one place, called static electricity, or it can be the type that is in a circuit which is called current electricity. First let’s look at static electricity.
If you ever slid down a plastic slide wearing certain types of clothing and noticed your hair standing straight out, guess what, static electricity again.
Don’t forget good old lightning! Yep, static electricity as well, only with much more power. Maybe 2 billion volts!
The number of volts is the amout of electricity. Static electricity caused by simply walking across the carpet when the air is dry can easily reach over 30,000 volts! Regular household voltage that you plug your lamps into is around 120 volts, and can actually kill you! So the static electricity sounds really dangerous doesn’t it? But the truth is, static electricity might sting a little, but other than lightning is normally harmless. Many people have been killed by a lightning strike.
Lightning is caused by a build up of static in the clouds. Sometimes it strikes from a more negatively charged cloud to a more positively charged cloud, causing a flash that we see in the sky, and the loud thunder that we hear. Other times it srikes between a cloud and the earth, many times causing some damage or even a fire. A lot of buildings have a lightning rod on top to prevent this damage.
Static electricity can be fun sometimes but to be useful, we need the type of electricity that can produce some current. The type of electricty we need is one that allows us to power things like our cell phones, laptops, refrigerators, and televisions, which basically comes in two types! We will talk more about the two types of current electricity in the next lesson.
Test your knowledge if you feel like it with a little test. No cheating now!
Q1: The nucleus of an atom contains neutrons and _____________.
Q2: The neutrons have a __________ charge.
Q3: Regular household electrical outlets have 120 _____________.