What You Want to Know about Electrical Laws and Formulas
written by: Mike Aguilar
• edited by: Lamar Stonecypher
• updated: 10/14/2011
Almost everyone knows the electrical terms volts, watts, amps, and ohms. Not as many people know about inductance, capacitance, impedance, or reactance, though. The informative articles linked below will reveal these mysteries of the electrical world ... and more.
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From Ohm’s Law describing the interrelationships between resistance, current, voltage, and power to Kirchoff’s Laws concerning power conservation, the laws governing and describing how electronic devices operate and utilize the electricity we give them are fairly numerous and very difficult for the uninitiated to understand. Add in variables such as “Q" Theory (transistor operation theory), impedance, capacitance and inductance, and these ideas and theories become even fuzzier and harder to understand. Whether you’re wanting to discover and understand this information for your own reasons, or you want to gain a better understanding in order to put a lesson plan together, you’ll read about these laws of electricity and more, and you’ll be given all of the formulas you need to do any type of electrical calculation you may need. You’ll also be given a plethora of information regarding Integrated Circuits (IC) and other types of digital circuits, such as AND and NAND gates.
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Basic and Advanced Electrical Laws- Ohms, Kirchhoff, and Thevenin
There are two basic laws that govern electrical theory. Ohm’s Law, named after Georg Ohm, the man that that discovered the interrelationship of electrical components in electronic circuits, is the main building block of most electrical theory and any circuit analysis. Ohm’s Law deals with the circuit parameters voltage (Volts; E or V), current (Amperage/Amps; I or A), resistance (Ohms), and, power (Wattage or Watts; W or P). If you know two of these values, you can calculate the other two.
Kirchhoff’s Law, named after Gustav Kirchhoff, who first postulated it, is also known as the Law of Conservation of Energy/Power. Referenced below, you will find information that will help you understand basic electronic theory and how to perform a circuit analysis, with all of the formulas you will need for this. Kirchhoff’s Law will be explained thoroughly. Thevenin’s Theorem for linear electrical networks is also referenced below. This theorem is named after Léon Thevenin, who re-discovered it after it was originally described by Hermann Helmhotz.
Understanding Electrical and Electronic Components
Electrical devices and circuits are made up of electronic components. Resistors, inductors, capacitors, diodes, and the many types of diodes are examples of typical electronic components. When you’re through with this section, you will have a complete understanding of a variety of these electronic components that make up common everyday electrical devices.
Various types of resistors, such as thermistors and potentiometers, and how to determine their resistance, are described below. You’ll also find information regarding capacitance and different types of capacitors, as well as inductors and inductance. The various types of diodes, such as zeners and light emitting diodes (LEDs), will be explained in detail. You’ll also be given information to help you understand the design, use, and function of relays, including the electronic relay phenomenom known as Hysteresis.
Understanding Transistors and Transistor Operation
Before the invention of the transistor in the 1950s, current and voltage switching and amplification was handled by vacuum tubes. But these components were very fragile and easily susceptible to failure from breakage. Transistors are examples of semiconductor devices that use multiple silicone junctions to control the flow of power in a circuit. There are a number of different types of transistors that are designed for different purposes, such as power amplifiers and power switching circuits. Some of these different transistor types are discussed in detail below.
Integrated Circuits- Devices That Make the World Go ‘Round
Integrated circuits (ICs) are semiconductor devices that are basically collections of complex circuits based on miniaturized transistors. These components can be found in almost every type of electrical or electronic device made today. The CPU in your computer or tablet (or smartphone, these days) is an example of a highly refined and advanced integrated circuit. Listed below you will find a number of topics about integrated circuits. The basics of ICs, including how they’re made, is referenced below. You’ll also find information on the major types, or families of ICs, the operation and use of ICs in electronic and electrical design, and where and how they’re used. There’s also information listed below about a specific type of IC used throughout your automobile as a sensor, the Hall Effect IC.
Referenced below is all you ever wanted to know about complex IC circuits such as gates and flip-flops.