Lesson 1: Electrical Basics

Imagine a dam. Behind the dam is a reservoir of water. The reservoir can be full or empty. The dam can let water out at a slow rate or a fast rate. If the reservoir is full, the POTENTIAL energy that is stored by the dam is high. In other words if the dam breaks, the amount of energy being released all at once would be quite large, and would overwhelm anything down stream. The dam is providing RESISTANCE to the flow of energy, and with out some form of resistance, there can be no potential. If the dam fills to capacity the resistance will begin to break down and allow the water to FLOW. We refer to the flow as CURRENT.

One can observe that the relationship between Potential, Resistance and Current is relative, that is to say that a change in one will affect another. If the resistance remains constant the current will change with the amount of potential change. Ah but what if the potential drops to the point that there is no current? I like to think of it as if there is always current of some amount. The dam will always allow a small amount of water thru even if it such a small amount that we cannot measure it.

In the world of electricity, the potential energy is measured in VOLTS while the resistance is measured in OHMS and the current is measured in AMPERS. The relationship between potential resistance and current is known as OHMS LAW. It states that Potential is equal to the Resistance times the Current. In formula form the potential is given the letter E to represent Energy. The resistance is given the letter R, and the current is give the letter I to represent Intensity. Therefore, in a calculation:

E=I*R, I= E/R and R = E/I

The potential is a charge normally developed by chemical relationships and contained in a storage device. Most often the device is called a battery, like the battery in your cell phone or watch. Just like the dam, the battery must have some potential for there to be a flow of current. If the battery has run out of useful current flow, we call the battery dead, and if it is possible to recharge that battery, we will attach it to a flow that will fill the reservoir.
NaoLoirasMais NaoLoirasMais
46-50, M
Dec 3, 2012