Introduction to Electronics Ohm's Law, quick introduction
This guide will help you understand electronic circuits—the fundamental building blocks of modern technology. Electronics are all around us, embedded in countless devices we use daily, and it all starts with these circuits.
Ohm's Law, quick introduction
Earlier in this course I gave you an introduction to a few fundamental concepts in electronics, such as Ohm Law and Kirchhof's Laws. Now, it's time to add a few more concepts to the list.
Understanding the behavior of electronic circuits begins with three fundamental concepts: voltage, current, and resistance. Let's break these down into simple terms.
Voltage, often referred to as electrical difference, is the driving force that pushes electric charge through a circuit. You can think of it much like pressure pushing water through a pipe. It's measured in volts and symbolized by the letter 'V'.
Current is the flow of electric charge in a circuit. It's the actual movement of electrons through conductors, like the water flowing through that pipe we mentioned earlier. Current is measured in amperes or amps and represented by the letter 'A'.
Resistance is the opposition to current flow within a material. Materials in a circuit can hinder the flow of electrons to varying degrees – this is resistance. It's akin to friction that slows down the water flow. Resistance is measured in ohms and denoted by the Greek letter omega (Ω).
These three are interrelated in a way that's defined by Ohm's Law, which states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points, and inversely proportional to the resistance (R). This relationship is neatly summarized by the formula:
I=VRI=VRI=VR
Think of a basic electronics circuit as a loop. The voltage source, such as a battery, provides the necessary energy. Electrical components, which could be anything from a light bulb to a resistor, regulate the current flow and control the output of the circuit. The resistance determines how freely current can flow, ultimately affecting the function of the device.
Concept
Symbol
Unit
Measurement
Voltage
V
Volts (V)
Voltmeter
Current
I
Amperes (A)
Ammeter
Resistance
R
Ohms (Ω)
Ohmmeter
INTRODUCTION TO ELECTRONICS
A comprehensive course to help you start your adventure in electronics. Solve circuits, simulate, and experiment on the breadboard.
Are you ready to dive into the fascinating world of electronics? Whether you're a hobbyist looking to build your first circuit, a student seeking a deeper understanding of how electronics work, or a professional expanding your skillset, this course is your gateway to mastering the essentials of electronics.
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