Passives Education

This calculator helps you compute the inductance of a coil.

The smaller the cross-sectional area of any given wire, the greater the resistance for any given length, all other factors being equal. A wire with greater resistance will dissipate a greater amount of heat energy for any given amount of current, the power being equal to P=I2R. Dissipated power due to a conductor’s resistance manifests itself in the form of heat, and excessive heat can be damaging

Pure resistive AC circuit: voltage and current are in phase. If we were to plot the current and voltage for a very simple AC circuit consisting of a source and a resistor, (figure above) it would look something like this: (figure below) Voltage and current “in phase” for resistive circuit. Because the resistor allows an amount of current directly proportional to the voltage across it at all periods of time,

Suppose you were to take a 3 kW electric heater rated for 240 VAC and connect it to a 120 VAC power source. How much power would it dissipate when connected to a voltage source equal to half its rating?

A three-phase motor may be run from a single-phase power source. However, it will not self-start. It may be hand started in either direction, coming up to speed in a few seconds. It will only develop 2/3 of the 3-φ power rating because one winding is not used. 3-φ motor runs from 1-φ power but does not start Single Coil of a Single Phase Motor The single coil of a single-phase

PARTS AND MATERIALS Several 10 kΩ resistors One 10 kΩ potentiometer, linear taper (Radio Shack catalog # 271-1715) CROSS-REFERENCES Lessons In Electric Circuits, Volume 1, chapter 5: “Series and Parallel Circuits” Lessons In Electric Circuits, Volume 1, chapter 7: “Series-Parallel Combination Circuits” Lessons In Electric Circuits, Volume 1, chapter 8: “DC Metering Circuits” LEARNING OBJECTIVES Series-parallel resistances Calibration theory and practice SCHEMATIC DIAGRAM ILLUSTRATION INSTRUCTIONS This experiment explores the different resistance ranges obtainable from combining fixed-value resistors with a

Wiring for AC and DC power distribution branch circuits are color coded for identification of individual wires. In some jurisdictions all wire colors are specified in legal documents. In other jurisdictions, only a few conductor colors are so codified. In that case, local custom dictates the “optional” wire colors. IEC, AC: Most of Europe abides by IEC (International Electrotechnical Commission) wiring color codes for AC branch circuits. These are listed

Don’t just sit there! Build something!! Learning to mathematically analyze circuits requires much study and practice. Typically, students practice by working through lots of sample problems and checking their answers against those provided by the textbook or the instructor. While this is good, there is a much better way. You will learn much more by actually building and analyzing real circuits, letting your test equipment provide the “answers” instead

The Q, or quality, factor of a resonant circuit is a measure of the “goodness” or quality of a resonant circuit. A higher value for this figure of merit corresponds to a more narrow bandwidth, which is desirable in many applications. More formally, Q is the ratio of power stored to power dissipated in the circuit reactance and resistance, respectively: Q = Pstored/Pdissipated = I2X/I2R Q = X/R

In this section, we'll be looking at RC and RL circuits. RC and RL circuits are nothing more than applications for resistors, inductors, and capacitors. We will primarily look at RC circuits since they are more commonly used and especially they're widely used with computers circuits and digital circuits which will be our focus. RL will be presented, but it will be in an abbreviated form. Characteristics with sine wave

Learning Objectives Rheostat use Wiring a potentiometer as a rheostat Simple motor speed control Use of voltmeter over ammeter to verify a continuous circuit Parts and Materials 6-volt battery Potentiometer, single turn, 5 kΩ, linear taper (Radio Shack catalog # 271-1714) Small “hobby” motor, permanent-magnet type (Radio Shack catalog # 273-223 or equivalent) For this experiment, you will need a relatively low-value potentiometer, certainly not more than 5 kΩ. Cross-References Lessons In Electric Circuits,

This calculator helps you compute the inductance of a rectangle loop.

Passive Devices Components incapable of controlling current by means of another electrical signal are called passive devices. Resistors, capacitors, inductors, transformers, and even diodes are all considered passive devices. Active Devices An active device is any type of circuit component with the ability to electrically control electric charge flow (electricity controlling electricity). In order for a circuit to be properly called electronic, it must contain at least one active device.

While Oersted’s surprising discovery of electromagnetism paved the way for more practical applications of electricity, it was Michael Faraday who gave us the key to the practical generation of electricity: electromagnetic induction. Faraday discovered that a voltage would be generated across a length of wire if that wire was exposed to a perpendicular magnetic field flux of changing intensity. An easy way to create a magnetic field of changing

PARTS AND MATERIALS Two single-turn, linear-taper potentiometers, 5 kΩ each (Radio Shack catalog # 271-1714) One single-turn, linear-taper potentiometer, 50 kΩ (Radio Shack catalog # 271-1716) Plastic or metal mounting box Three “banana” jack style binding posts, or other terminal hardware, for connection to potentiometer circuit (Radio Shack catalog # 274-662 or equivalent) This is a project useful to those who want a precision potentiometer without spending a lot of money. Ordinarily, multi-turn potentiometers are

The circuit in the previous section is not a very practical one. In fact, it can be quite dangerous to build (directly connecting the poles of a voltage source together with a single piece of wire). The reason it is dangerous is that the magnitude of electric current may be very large in such a short circuit, and the release of energy may be very dramatic (usually in the form

∫f(x) dx Calculus alert! Calculus is a branch of mathematics that originated with scientific questions concerning rates of change. The easiest rates of change for most people to understand are those dealing with time. For example, a student watching their savings account dwindle over time as they pay for tuition and other expenses is very concerned with rates of change (dollars per year being spent). In calculus, we have

Pure resistive AC circuit: resistor voltage and current are in phase. If we were to plot the current and voltage for a very simple AC circuit consisting of a source and a resistor (figure above), it would look something like this: (figure below) Voltage and current “in phase” for resistive circuit. Because the resistor simply and directly resists the flow of current at all periods of time, the waveform for

Using the same value components in our series example circuit, we will connect them in parallel and see what happens: Parallel R-C circuit. Resistor and Capacitor in Parallel Because the power source has the same frequency as the series example circuit, and the resistor and capacitor both have the same values of resistance and capacitance, respectively, they must also have the same values of impedance. So, we can begin our