A resistor is a two-terminal passive electrical device that opposes current flow. It is most likely the most basic component in an electrical circuit. Resistance is present in practically all electronic circuits, making it one of the most prevalent components. Typically, they are color-coded.
A. Structure
Because resistance is a natural feature of practically all conductors, a resistor isn’t a complicated gadget at all. A capacitor is made out of a copper wire that is wrapped around an insulating material like a ceramic rod. The resistance is proportional to the number of turns and the thickness of copper wire. The resistance increases as the number of turns and wire thickness increase.
Resistors built of a spiral pattern of carbon film are also available. Carbon film resistors get their name from this. Carbon film resistors are not as exact as wire-wound competitors, thus they’re best for low-power circuits. They are, nonetheless, less expensive than connected resistors. Both ends of the wire are connected with wire terminals. The electricity can flow in either direction via resistors since they are blind to the polarity in a circuit. As a result, there’s no need to be concerned about whether they’re attached front or backward.
B. What Is It and How Does It Work?
A resistor may appear to be insignificant. It may appear like it does nothing but devour energy. It does, however, serve an important purpose: it regulates the voltage and current in your circuit. Resistors, in other terms, allow you control over the layout of your circuit.
When an electric current is applied to a wire, all of the electrons begin to move in the same direction. It’s the same as water running through a pipe. Because there is less room for water to go through a thin pipe, less water will flow through it.
When current travels through a small wire in a resistor, the electrons find it increasingly difficult to wiggle through it. In other words, as the length and thinness of the wire grows, the quantity of electrons flowing through the resistor decreases.
C. Purpose and Importance
The three most typical applications for resistors are regulating current flow, splitting voltage, and resistor-capacitor networks.
Controlling Current Flow
Current will flow at dangerously high levels if resistors are not added to a circuit. It has the potential to overheat and damage other components. An LED, for example, might be connected directly to a battery and still function. However, after a while, the LED will become as hot as a fireball. Because LEDs are less heat tolerant, it will eventually burn.
However, if you add a resistor to the circuit, the current flow will be reduced to an optimal amount. As a result, you can leave the LED on for longer without it overheating.
Voltage Division
To lower the voltage to the required level, resistors are also utilised. A specific component in a circuit, such as a microcontroller, may require a lower voltage than the circuit as a whole. A resistor is used in this situation.
Assume your circuit is powered by a 12V battery. The microcontroller, on the other hand, simply requires a 6V supply. To divide the voltage in half, simply connect two resistors with the same resistance value in series. The cable connecting the two resistors has cut the voltage of the circuit where the microcontroller can be connected in half. You can lower the voltage in the circuit to any level by using appropriate resistors.
Networks of Resistor-Capacitor
Resistors and capacitors are also used together to make ICs with resistor-capacitor arrays on a single chip. RC filters and RC networks are other names for them. They are frequently used to suppress electromagnetic interference (EMI) or radio frequency interference (RFI) in a variety of instruments, including computer and laptop input/output ports, LANs, and WANs, among others. Machine tools, switchgears, motor controllers, automated equipment, industrial appliances, elevators, and escalators are all places where they’re utilised.
