I am planning on writing a series of blogs which were inspired by how I would answer questions about electronics/electrical principles in a very simplified way so that I can explain these principles to my first grader. Here is the first in the series about voltage and current using a simplified analogy with water. Even though some might disagree with using this analogy, I think this is instructive to explain the basic concept.
Why should you learn about electric voltage and electric current?
There are electrical devices all around us from washing machines to flat screen TVs to smartphones. All electrical equipment works on some kind of electrical energy source that involves a voltage and a flow of current. To understand the complex, you have to understand the basic fundamental principles on which it works. Hence, it is important to understand the fundamental concepts of electric voltage and current.
The simplest way to understand voltage and current is to make an analogy with water pressure and the flow of water. Think of the water tank in your neighborhood. Why is this tank placed at a height? This is so that the water is at a certain pressure due to gravity (Aside: each foot of height provides 0.43PSI). Why does the water need to be at a certain pressure? So we can do some useful work with it. Now suppose you were to connect a pipe at the bottom of this tank, what would happen? Water would start flowing in the pipe to the ground due to gravity. I think you can see where I am going with this….the water pressure is analogous to electric voltage, sometimes called electro motive force or e.m.f. The flow of water is analogous to electric current. There are various ways we can get this electric pressure or voltage. The one most people are familiar with is by using a battery. Think of a battery as a “tank” that is providing you with the pressure you need or electric voltage. Just as water will flow when we connect a pipe to the tank, an electric current will flow in a wire when we connect a wire to the battery.
In the next post I will talk about the concept of a short circuit and open circuit using this same analogy. Let me know if you found this analogy useful.