Circuits

When considering electricity,

Current (measured in Amps) is often considered the flow of energy.

The force behind the flow is the Volts.

While the volts can be measured between any two points in the circuit (open, or closed), measuring the current, or flow of energy typically requires interrupting the flow.

Somewhat like water. One can measure pressure of the water on a branch, but one must have a way to monitor the actual flow to determine how much water has passed.

There are "exceptions" though.

If you have an AC circuit, then an inductive ammeter can measure the amps around a single leg if the circuit without being installed inline with the circuit.

Even with a DC circuit, it may be desirable to design a bypass or shunt circuit so that the majority of the current bypasses the ammeter, and only a small amount of the current actually flows through the ammeter.

The typical ohmmeter measures DC resistance by providing DC current and measuring the voltage drop accross the resistor. By definition, the 'ideal' capacitor is an open circuit to DC current and voltage. By definition, an open circuit has infinite resistance.

Of course, real-world capacitors are not ideal. They have a very high parallel leakage resistance and a very small series resistance. And, different meters can measure different ranges of resistance. So, you may not get an infinite/overload measurement on some capacitors with some meters. You may get a very high resistance instead. If so, you are not really measuring the resistance of the 'capacitor', but rather that of the imperfections in the component manufactured to be a capacitor.

ANSWER: The ohmmeter battery will charge the capacitor in 5 time RC after that it quirts there is no more current flow. Any body that claim to be able to check resistance of a capacitor i just a wannabe

Sadly, this website doesn't support graphics.

Please note that resistivity also depends on temperature.In the most general case, the answer is definitely NO; all superconductors have the same resistivity, namely zero.

Other than superconductors, take a look at a table with some typical resistivity values. It would seem quite obvious that for a given temperature:

* Two different substances will, in general, have different resistivities.

* In practice, in some cases the difference in resistivity might be too small to reliably measure.

* It should be possible to find two substances that have the same resistivity at a very specific temperature - since the temperature-dependence will vary from one material to another.

* Likewise, it should be possible to design a mix of two substances, which exactly matches that of another, given, substance.

A relay circuit is typically a smaller switch or device which drives (opens/closes) an electric switch that is capable of carrying much larger current amounts. Or a circuit which operates the coil or electronic actuator from one source and uses a separate power source to drive an isolated device. Generally speaking, a relay circuit is a circuit that uses a small mechanical switch or a semiconductor device (with associated circuitry) to energize a relay, which will then close a contact set to complete another circuit. This system is used by most people on a daily basis, and it is used to start a motor vehicle. The key switch (ignition switch) is turned to "start" and 12 volts (approximately) is applied to the starter solenoid (which is a big relay). The coil is energized, it shuts contacts, and the battery voltage is delivered through the heavy contact set (for high current capacity) to the starter motor. There are variations on this theme to which the term relay circuit can be applied, but the idea remains the same: a small switch of some kind controls switching in another (usually higher voltage and/or current) circuit. It could be argued that the telegraph is a relay circuit. Remember those old westerns? When a telegraph key is pushed down (thus completing the circuit), a remote (relay) coil is energized. The magnetic field created by energizing that coil pulls down an armature with the objective being to make a "click" instead of it being to close some electrical contacts. An early and dramatic application of the simple relay circuit, the telegraph, yes? A RELAY CIRCUIT DOES NOT IMPLY MASSIVE CURRENT SWITCHING. It is a means to isolate one source to another.

Usually, in electric theory and circuits, the components of an electric circuit are called "elements"... however, depending on the subject matter, the answer could vary from electrons, current, or voltage to something like wires, integrated circuits, chips, or even lead!

DC does not travel through a capacitor for long because there is a buildup of charge on the plates and when the voltage matches the supply voltage, mo more current flows.

But capacitors are used to smooth a DC supply because a capacitor acts a bit like a small battery and can prevent any rapid fluctuations in the supply voltage.

a digital input accepts a voltage level between 0 ( zero and 5 volts +

the digital circuitry is designed to accept a logic 1 or a logic 0 signal .

the logic 1 is equal to 5 volts optimum , but a tolerance is allowed.

the logic 0 signal is around 0 volts, to a limit of 0.8 volts.

thus a digital signal is designed to be at 2 distinct points or levels of measurement.

by comparison an analogue signal can be varying around a designed level.

the input signal is likely to vary and the cirucit inputs are designed to analyse and measure these signals.

Three things that an electrical circuit must have to operate is,

A) a source. Example- battery

B) a line. Example- conducting wires that allow the electricity to pass through

and C) a load. Example- A light bulb

It is an circuit that is used to find the value of the resistances. The main principle behind it is the balancing an circuit by means of varying an resistance on connected to an arm of the circuit.When the resistance become equal to the variable resistance no current flows thus we can find the value of the resistance.

FET is abbreviation of Field Effect Transistor. This is a transistor in which current is controlled by voltage only and no current is drawn. It is a high input impedence device and is used in computers, telecommunication and control circuits. This transistor is better in certain parameters as compared to BJT, that is Bipolar Junction Transistor.

No way of telling. to get amps you have to have a current flow, which you get when you connect a consumer to an outlet. Then the consumer will pull amps according to its wattage rating (Watts / Volts = amps) - assuming it's all hooked to a fuse with enough rating.

The invention of the capacitor varies somewhat depending on who you ask. There are records that indicate a German scientist named Ewald Georg von Kleist invented the capacitor in November 1745. Several months later Pieter van Musschenbroek, a Dutch professor at the University of Leyden came up with a very similar device in the form of the Leyden jar, which is typically credited as the first capacitor. Since Kleist didn't have detailed records and notes, nor the notoriety of his Dutch counterpart, he's often overlooked as a contributor to the capacitor's evolution. However, over the years, both have been given equal credit as it was established that their research was independent of each other and merely a scientific coincidence.

The Leyden jar was a very simple device. It consisted of a glass jar, half filled with water and lined inside and out with metal foil. The glass acted as the dielectric, although it was thought for a time that water was the key ingredient. There was usually a metal wire or chain driven through a cork in the top of the jar. The chain was then hooked to something that would deliver a charge, most likely a hand-cranked static generator. Once delivered, the jar would hold two equal but opposite charges in equilibrium until they were connected with a wire, producing a slight spark or shock .

Benjamin Franklin worked with the Leyden jar in his experiments with electricity and soon found that a flat piece of glass worked as well as the jar model, prompting him to develop the flat capacitor, or Franklin square. Years later, English chemist Michael Faraday would pioneer the first practical applications for the capacitor in trying to store unused electrons from his experiments. This led to the first usable capacitor, made from large oil barrels. Faraday's progress with capacitors is what eventually enabled us to deliver electric power over great distances. As a result of Faraday's achievements in the field of electricity, the unit of measurement for capacitors, or capacitance, became known as the farad.

1) a bridge based on the principle of Wheat stone's bridge that is

used to compare two nearly equal resistances and to determine values of low resistances

and the specific resistance of a wire. It differs from a meter bridge because additional

resistances of similar magnitudes are included at either end of the meter wire.

Some capacitors are polarity sensitive; some are not. It depends on the design. Electrolytic capacitors, for instance, are polarity sensitive, while ceramic disc capacitors are not. You can generally tell, if the capacitor is marked with polarity signs, such as + and -, if it is or not.

Resistance of a conductor is defined by the specific resistivity, area of cross section and the length of the conductor. R = rL/A, where R is resistance in OHMs, r is specific resistance, L length in mm, A is area of cross section in sq mm

A very very tiny amount of the current that would normally flow through the resistor instead flows through the voltmeter, allowing it to make its measurement. For most purposes this very very tiny amount of current can be completely ignored.

Everything that goes on in an electrical circuit happens in response to a

flow of electrical current. Electrons are the carriers of electrical charge

whose motion constitutes the electrical current in the circuit.

A non-stationary signal is one whose frequency changes over time; e.g. human speech where frequencies vary over time depending on what words or syllables you are pronouncing. On the contrary, you have stationary signals where frequencies don't change over time; e.g. the signal: cos(20*pi*t)+cos(50*pi*t)+cos(200*pi*t) where all of the frequency components (20*pi, 50*pi, 200*pi) exist at all times.