Voltage, Current and Resistance?

Hey Folks. After quite lot of thinking, here I come up with yet another analogy. This time to relate to basic terms used in Electronics: Voltage, Current and Resistance. What are they really? How do I relate to it?   Keep reading...

Firstly, let me have for you their simple definitions.

Voltage is the potential difference between two points. That is if a point say "A" is at 15V and another point "B" is at 5V, then there is a +10V potential difference between points A and B. That is, Vab = 10V. Voltage is measured in Volts (V).

Current is the flow of electric charges through a certain medium normally due to voltage gradients (difference) between two points. In the above example, since there exists a voltage difference between points "A" and "B", electron flow occur from "B" to "A" (since "B" is more positive and electrons are negative charges). Remember that electron current travel in direction opposite to that of the electron flow and hence travel from "A" to "B". Current is denoted by symbol "I" and measured in Amperes.

Resistance is the degree or measure of obstruction that an object provides  to electric current when passing through it. Hence more the resistance of a medium, the lesser will it allow current to flow through. It is denoted by symbol "R".

Further, all these three parameters can be related to each other using a famous equation called the OHM'S LAW. The law states that, for an ideal conductor, V = I x R. This is not difficult keep in mind..    Higher the resistance => Less Current    Also Higher the resistance ==> Higher potential drop.

Well, I am sure you must be feeling quite dizzy by now! How do you remember/correlate these things? Below is my analogy..

I chose a see-saw to demonstrate since I am sure most of you at your early times would have used it for sure. Now, assume that Person1's weight is the voltage at point A and Person2's weight is the voltage at point B. If their weights are the same, the see-saw does not move. To see a see-saw in action (and thats the fun part), you need to have different weights.

The difference is weights can be thought as a difference in Voltage between those 2 points A and B and the motion of see-saw as the current flowing. The direction of motion of the see-saw will then indicate the direction of current (Higher weight to the lower one). However the motion of the see-saw is dependant on the pivot. The tighter it's screws are, the lesser it would move though you have got a differential weight. The pivot is the Resistance!

So, in summary here.. Voltages are analogous to weights of people, Current flow is analogous to movement of see-saw (direction too) & Resistance is analogous to the pivot holding the see-saw. As simple as it is!