Oxygen

Chapter 1

What Is Electricity, Anyway?



Introduction
Chapter 1 - Electricity
Chapter 1.2 - The Numbers

Chapter 2 – Sharing and Bonding

Chapter 3 - Voltage
Chapter 3.2 – Voltage Static
Chapter 3.3 - Batteries
Chapter 3.4 – Solar - Others

Chapter 4 - Resistance
Chapter 4.2 – Parallel Resistance
Chapter 4.3 – Voltage Dividers

Chapter 5 - Semiconductor
Chapter 5.2 - PNP NPN Junctions

Chapter 6 – AC and Hertz

Chapter 7 - Magnetism
Chapter 7.2 - Inductors

Chapter 8 - Capacitor

Chapter 9 - IC's and Amplifier

Chapter 10 - 555 Timer

Chapter 11 - Logic

Chapter 12 - Power Supply

Energy - On The Move

So what is Electricity? The simple answer is that electricity is a form of energy not so different from that of sun light or heat energy. However, with all things in science and nature, a simple answer does not fully answer the question. Especially if you really want to study this field. Electricity is the flow of electrons for one point to another. It is the result of something else happening. This makes electricity a secondary source of energy. That is, it takes some primary change in energy to produce an action, that causes electron movement (electricity).

There are many primary energy changes that cause electrical energy (electricity). Here are two examples to get you started.

  • When a chemical reaction takes place inside a battery, the primary energy change is the chemical change, and that change can generate electricity.
  • When a change in a magnetic field intersects a copper wire, that action can generate electricity.

  • There is more to learn about in each of these actions, but for now, just reflect on the idea that one something happens (the primary change) and that event ends up generating electricity.

    Chemistry and Physics Behind It All (STEM)

    Much of science and technology uses fundamental knowledge borrowed from or shared across many other fields of study. We see this show up in our every day lives. One example is that we do not consider the chemistry or the physics that goes into a grocery bag design. We just want to carry our groceries home from the store. But when that bag rips, we experience the impact of the decisions someone else made about the bags materials and its construction.

    Electricity is no different. Flip a switch and the room light goes on. We simply want to use the technology without thinking about it. However, in this study to goal is to understand the inter-workings of this technology. To do so we need some foundational knowledge to build upon. As you move through this book, it will provide a cursory look into other fields in science, technology, engineering, and mathematics as they relate to the topic at hand.

    Starting Off Small:

    An ATOM is made up of small parts called subatomic particles. Some of these subatomic particles have names like electron, proton and neutron. An electron has a negative (-) change. You can think of each electron as carrying one unit of negative charge. The electrons counter-part is the proton and it has a positive (+) charge. A third subatomic particle, the neutron, has no charge. Except for Hydrogen, which has no neutron, the combination of two or more protons and that same number of neutrons makes up the center, also called the nucleus, of the atom. Atom To keep an atom with a neutral charge it will have the same number of electrons (negative charge) as it has protons (positive charge). The electrons are busy flying around the nucleus in orbit called a cloud or shell.

    In earlier scientific studies of atoms and their structure, the scientists discovered that there is a relationship between the number of shells and the number of electron-proton-neutron sets. A few basic facts about each element are listed in a special table of facts called the periodic table. For example, the first element in the table (atomic number 1) is Hydrogen with one electron, one proton and one shell. (Hydrogen has no neutron) The second element in the periodic table is called Helium. This element (atomic number 2) has a set of two electrons, two protons, and two neutrons and still only one shell. These two elements, Hydrogen and Helium are the only two elements with a single shell arrangement. Atoms with larger atomic numbers may have as many as four, or five or six electron shells. With the larger numbers of protons and neutrons in the nucleus, at specific points, an additional shell is needed to hold the orbiting electrons in their respective orbits. Regardless of the number of shells, only the outermost shell in any element is called the valence shell, and the electrons in that shell are called the valance electrons.

    Before we dig into the topic any further, we will want to have a basic understanding of how numbers are used in electronics.


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