Electronics Engineering

A semiconductor works by allowing certain voltages to pass through a circuit and not others. The simplest semiconductor is a diode.

yes of course

The formula you are looking for is, R = Volts (squared)/Watts.

There are two kinds of transformers, autotransformers and isolation transformers. An autotransformer has one coil, an isolation transformer has at least two. To find the output voltage of a transformer, you need to know three things. First is the input voltage. Next are the number of turns on the primary coil, and last is the number of turns on the secondary coil. So! Our input voltage is going to be 120 in all three of the cases I'll give, and the number of turns on the primary coil will be 120--this makes the math easy, although you aren't restricted to putting 120 turns of wire in a 120v primary. You can put a million turns on if you want, and I've seen it. If our secondary has 12 turns, the output voltage will be 12--there is a 10:1 primary:secondary ratio. Normally this is called a "stepdown" transformer. It's used when the device requires less than line voltage to operate. A secondary with 120 turns will give a 120v output voltage. This is an "isolation" transformer. You use this as a safety device. Secondaries with 2500 turns give a 2500v output voltage--perfect for radio frequency amplifying tubes like the 4CX250A. For extra entertainment let's talk about the autotransformer for a minute. As I said above, this has one coil. It's tapped. If you've got 220v coming into a 220-turn coil and there's a tap at 110 turns, you're getting 110v out of it. Every soldier stationed in a country that uses 220v power buys one of these from the local post exchange so he can use the TV set he brought from home.

Use of an Ohm Meter is the best, and only way I can think of, to test any kind of short circuits. Since you used the word track in the question I'm guessing this is a model train problem. The first thing to do is check the voltage at the transformer (electrical source). Then check the Ohms of each track. This will tell which track has the short. Moving one test lead up the track should locate the short. I the train doesn't move when the power is applied, the problem is probably a broker solder point.

No worries. The important thing here is that this module is simply reading a voltage from the sensor with reference to the ground of that sensor. This means that this module is always going to be a sinking device, and will be always be sinking small amounts of current from that sensor. This means, that your sensor is going to be powered externally and we will simply be reading the output voltage from it. Here is a link to a knowledgebase article about sinking and sourcing current. I hope this helps to clarify.

In the ohm's law formula we have, volts (V), amperes (A) and ohms (omega). There is no time in it. Scroll down to related links and look at "Ohm's law - calculator and formulas".

(the current in the earth direction is going left of use) 8th grade studend juicey babee

Possibly. If it still works when you turn it on, the of course it is using power. If it does not work when it otherwise would, then it is definitely not using power, just as if you didn't have the bulb there at all.

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With the voltage on the circuit and the light bulb in the circuit, the bulb will glow. If you unscrew the bulb until it goes out the potential voltage will still be in the circuit but no current will flow so no power will be used. In this scenario the unscrewing of the bulb will be the same as using a switch in the circuit to interrupt the current flow.

Ummmmmmmm Not sure. I think it might have been a gye named david.

32 kHz

If you connect bulbs in parallel across a given voltage supply (eg household mains supply) then they will all draw their rated current and will glow at their rated brightness. If you connect the same bulbs in series then they will glow very much less brightly. This is because the resistance of a bulb's element is also related to the power dissipated in the element.

A bulb's element is rated for operation at a particular voltage. You can certainly connect two 6v motorcycle bulbs in series, and connect them to a car battery at 12v, and the two bulbs will be just as bright as they were when individually operated from the motorcycle 6v batttery. However if you connect two 6v bulbs in parallel and then wire them to a 12v car battery they will only glow brighter for a fraction of a second and then ... pop. You will have overheated the elements beyond their designed power handling capability.

as a buffer circuit... means whenever u need a high current....

e.x-> if u wnat to run a 12V relay using a PC parallel port(DB-25) output, u kan use such a TTL IC.... if u just connect the relay it will never switch!! the current in a parallel port output will just be enough to light 2 series LEDs....

ULN**** ICs are used in circuits that use PIC ICs(micro controller)..... Also ULN**** series ICs has low power dissipation...

-R-

For an ideal current source, this means replace the current source with an open circuit. Resistance can then be calculated across the terminals.

V = IR

Voltage (V, measured in volts) = Current (I measured in amps) times Resistance (R, measured in Ohms)

Is your current 3.13? I'm not sure what you wrote there, but just multiply your current times your resistance.

DATE: 17-MAY-12

THE CAPACITIVE REACTANCE VARIES INVERSELY WITH THE AMOUNT OF THE PRODUCT OF MAGNITUDE OF THE SUPPLY FREQUENCY, TWICE THE VALUE OF CONSTANT PI AND THE MAGNITUDE OF CAPACITANCE. IN OTHER WORDS, EVERY

TIME YOU INCREASE ANY OF THESE FACTORS OR IF SAY YOU FIX THE VALUE OF CAPACITANCE TO SAY 1 MICROFARAD AND OTHER FACTOR (i.e. 2 x PI) AS CONSTANT ALSO, BUT THEN WHEN DOUBLING THE FREQUENCY, SO THEN THE EFFECT TO THE CAPACITIVE REACTANCE WILL BE INVERSELY OR HALVED. THE MORE YOU INCREASE THE FREQUENCY, THE SMALLER THIS VALUE WILL BE. WHICH IN EFFECT ALLOWING MORE HIGH FREQUENCY CURRENT OR VOLTAGE TO PASS THRU THE CIRCUIT. AND THE REVERSE IS TRUE, MEANING ONCE YOU ALLOW LOW FREQUENCY CURRENT, THEN THE CAPAICTIVE REACTANCE WILL INCREASE AS A RESULT.

BY FMSJr. / ABU DHABI, UAE

The technologists design, and draft the electrical network from the ground to each outlet. The technician and the artisan are the same. They install and repair the electricity in the building.

Yes, electromagnetism is a central factor in the Cathode Ray Tube. An electron emitter at the back of the Cathode Ray Tube (CRT) fires electrons toward the front of the tube. These electrons pass through two sets of parallel metal plates - one set is oriented horizontally and the other vertically. The CRT creates a variable strength electromagnetic field across each pair of plates, and as the electron passes between the plates, the trajectory of the electron is deflected up, down, left, and/or right - depending upon the polarity and magnitude of the magnetic field between the plates. By deflecting the trajectory of the electrons so, the CRT can selectively and accurately aim electrons at specific points, or dots, on the front of the CRT. The inside front surface of the CRT is coated with a photo luminescent material that emits a photon (light) of a specific frequency (color) when struck by the electron. By selectively coating materials that emit red, blue, and green light for each dot, or pixel, the CRT can create a broad range of colors. The deflector plates cause the electrons to scan left to right (when looking at the picture) starting at the top line, then left to right on the second line, and so on, until it scans left to right on the very bottom line. The CRT resets the deflector plates again to start at the top left dot, and repeats the cycle for the next frame. This process is called a progressive raster scan. Most television signals use an interleave scan, where the CRT scans left-to-right on all the odd numbered lines first, then resets to the top-left corner, and next scans left-to-right all the even numbered lines last to scan a frame. Thus, in an interleaved raster scan, it actually takes two successive scans to display a complete frame. On a North American television, that uses NTSC format, the television scans 525 lines per frame (486 visible lines), 30 frames per second. A link to the Wikipedia article on the CRT is provided.

Metals are good conductors of electricity. Insulators are bad conductors of electricity. Similarly, semiconductor devices are partial conductors of electricity means their conductivity lies between conductors and insulators.

A; PWM is extensively used in PWM power supply whereby a fix frequency is setup but the duty cycle change to transfer power. Actually the maximum power is transferred during the rise and fall of the square wave

When p-n junction of a diode reversed biased then majority carriers are not able to cross the junction and are attracted in respective regions.So current becomes approximately zero.But because of minority carriers a reverse current keeps flowing.It is called Reverse Saturation Current.And due to attraction towards sides,charges go away from junction.So width of depletion reason increases.

when ever current passing through any two parallel transmission line than due to the dieletric property of conductor some what capacitance effect will be generate between them that phenomina called as capitance reactance/////////////////// that symply we can called capitance reactance is measure of capitance

The reactance of a capacitor is its resistance.

for germanium it is 0.3

and for silicon it is 0.7

Yes, but it's at a different frequency than your internet. Chances are before you got FiOS your internet and phone still used the same fiber optic cable.