Ok, I wanted to create this for a long time but never got around to sitting down to compile my thoughts on it. I know this is as basic as it gets, but I still wanted to put out a series of posts on everything I know about resistors. Hey, for most in my circle, this might not be the most exciting series, but believe me, while researching this topic, I stumbled upon a few things I didn’t know even after 18 years in this field!
Let’s start then. At its core, resistance is the property of a material that opposes the flow of electric current. But what does that mean from first principles? Imagine a river flowing downstream. If there’s no obstruction, the water flows smoothly. Now add rocks, debris, and narrow passages, the flow slows down. In an electrical circuit, electrons are the water, the material of the conductor is the riverbed, and resistance is the obstruction caused by the material’s atomic structure.
Electric current flows because electrons are pushed through a conductor under the influence of an electric field. However, as these electrons move, they collide with atoms and other particles within the material. These collisions are what create resistance, converting some electrical energy into heat. More frequent the collisions, the higher the resistance.
This phenomenon is beautifully captured by Ohm’s Law, which states that V=IR, where V is the voltage difference, I is the current, and R is the resistance. It tells us how much current will flow for a given voltage across a resistor(Applicable only if the temperature is constant). Now Resistors are just physical devices specifically designed to exhibit and control this property. They are put in circuits to intentionally control current flow and divide voltages.
So, as simple as the concept of resistance may seem, it’s at the heart of almost everything in electronics. Everything on the planet has resistance. Hopefully, in the coming posts, I will like to explore resistors from every angle that I know of.
BTW: Did you know that the smallest resistor ever made is less than a nanometer in size and made of a single molecule?
0 Comments
Comments are closed.