Consumer Electronics

I can think of two ways to do that:

1). Place a burning candle near a photovoltaic (solar) cell. The cell will convert
some of the heat and light energy from the candle flame to electrical energy.

2). This one is more complicated and takes more ancillary peripheral stuff.
-- Use the burning candle to heat and boil a container of water.
-- Guide the steam from the boiling water through the fan of a small turbine generator.

Advantages:

You can find anything you want in a store that has variety of things. Most departmental stores will have just about anything you're looking for, from clothes, to pharmaceutical products to food. We're living in a fast paced nation where we want to find things fast and get through our bidding quicker. You'll also find many products to be cheaper, for examples Walmart has many products cheaper than most stores although may vary because they can afford to place it to be cheaper because the demand is higher.

Disadvantages:

There's also disadvantages because many products may not be there, especially products that many other foreigners may want to use. Instead they'll probably have to export. Also because departmental stores carry everything many people will go to them causing traffic, parking dilemmas, and long waiting lines.

Economically:

Many people opening little local stores find themselves competing with large departmental stores, which in turn have them only buying what is needed to meet the demand of the people surrounding.

Reverse polarity is the opposite of normal polarity. Normal polarity in electronics is when you have the positive hooked up to the positive terminal and the negative to the negative terminal. Reverse polarity would be having the positive hooked up to the negative terminal and the negative to the positive terminal. The same concept can be used with magnets.

7812 is not a transistor. It is a three lead voltage regulator integrated circuit. Its maximum input voltage should be near 35 volts. The minimum input voltage should be near 14 volts. The output will be 12 volts.

OK, well Earth Loop Tester have a permanent magnet in it. When we rotate it, the flux cut the the conductor and consequently an emf is produced. As we connect the two point of the tester to the earth it complete the circuit and current start flowing through it.

The ratio of voltage and current give us the Impedance of Earth.

It was developed by Dr. Sam Hurst. He invented the first touch sensor which was not transparent and hence not like the touchscreens like today in 1971 at Kentucky University.

In 1974, he developed transparent touchscreens we use these days and in 1977 the whole technology used today was developed and patented it.

Let's look at a transformer first. Transformers are essentially two coils that are wrapped (wound) around a common core. The primary is supplied with a changing voltage. This develops a changing magnetic field in the core. And this changing magnetic field in the core "sweeps" the secondary windings and generates a voltage in those secondary windings. The changes in the primary due to the changing voltage are inductively coupled into the secondary to generate voltage there. The general answer to why a transformer doesn't work on a DC supply is that a DC voltage doesn't "change" and cause changes in the magnetic field in the core, and, thereby, cause changes in the voltage in the secondary windings. When we "turn on" the DC (direct current), a field will be built in the core, it will sweep the secondary windings and deliver a "pulse" as the field is built. But then the secondary voltage will drop to zero after the pulse. This is because there is a static magnetic field around the secondary windings, and a static field will not sweep the windings and generate a voltage. There will be no secondary voltage. It is possible to generate pulses of voltage in a transformer by pulsing a DC voltage supplied to the primary. The ignition coil in an automobile works in this way. The 12-volt supply is pulsed to the coil to generate the high voltage to fire the spark plugs. It is possible to get a transformer to work on DC. But, in general, transformers need a dynamically changing voltage supplied to them to cause the changing magnetic field in the core. This changing magnetic field will sweep the secondary windings and generate a changing voltage there. AC (alternating current) works really well for this application, and we use this idea in the power grids around the world.

An AC motor is an electric motor that runs on alternating current, like household electricity, as opposed to a DC motor that runs on direct current from a battery.

Most AC motors work from the mains supply, which has a frequency of 50Hz in the UK and 60Hz in the USA.

Other types are available that work like stepper motors and need a specialist supply to run them.

A: ZENERS are nothing else then regular diode that have a very predictable reverse breakdown voltage of xx volts. This voltage can be used to limit the input voltage or regulate on it.

Radios, Televisions & Computers.

.7v less than unity for DC operation but unity for AC.

by noticing the polarity of theohmmeter a diode can be checked for continuity and blocking ability However it will not tell you how good or bad the device itself is

BY keeping the multimeter in diode mode and keeping properly the positive and negative terminals of the multimeter. If the diode is good multimeter will show a reading of 0.5 else there will be a short.

A transistor has three leads, called the base, the collector, and the emitter. The voltage of the base (in relation to the ground) determines whether and how much current flows from the collector to the emitter. An NPN transistor can be off, meaning that there is no (or very little) voltage from the base; partly on, meaning that there is some voltage from the base; or saturated, meaning that it is receiving full voltage from the base. A saturated transistor allows the current to flow from the collector to the emitter unopposed; a partly on transistor provides some resistance; and a transistor that is off provides full resistance. A PNP transistor is similar to an NPN transistor except it performs the opposite function: when it is saturated, the current is fully resisted; when there is no voltage from the base, the current is not at all resisted; and when it is partly on there is some resistance.

In sum, a transistor controls the flow between the collector and the emitter based upon the voltage of the base. this is carbage. a transistor is basicaly two diodes back to back base being common TO BOTH DIODES because of inpurity doping on purpose at the depletion region the transistor will control the current flow on the other diode. Once it reaches saturation both diodes conduct therefore current can flow in BOTH DIRECTIONS ACROSS IT.

With today's auto-ranging meters, you might well ask why. Today meters do that for you, and you might see it happening on some of them.

In older meters, analog types in particular, you had to start with a higher range to be sure you didn't peg the meter measuring say, 220 volts when on the 10 volt scale. Lots of meters where toasted this way, their needles bent, or fuses blown by overcurrent. On higher ranges, the meter would deflect slightly, indicating there was voltage there, but not enough to get a accurate reading. So you scale down until hopefully you get a reading somewhere in mid scale, where the most accurate reading can be made.

So the use was to protect the meter from damage, and provide the most accurate reading possible from an analog meter.

Voltage is a defined as a difference in potential. So to measure voltage, you need to look at the difference in potential between two different nodes in a circuit. For example, to know the voltage of a capacitor, you are looking at the difference in potential from one terminal of the capacitor to the other. Even if it is installed in a circuit. It is for this reason, that the measurement is across the circuit, or in parallel with it. One common point of confusion in voltage measurement is the way it is presented. Someone will say, that wire is at 5 volts. The "with reference to" part is often left off. We can say this because most circuits have a direct or implied ground, that all other voltages are referenced to. So the correct thing to say would be "that wire is at 5 volts to ground."

Over Current (Inverse Time) Over current relay function monitors the general balanced overloading and has current/time settings. This is determined by the overall protective discrimination scheme. There advantage over definite time relays is that they can have much shorter tripping times can be obtained without any risk to the protection selection process. These are classified in accordance with there characteristic curves, this indicates the speed of the operation. Based on this they are defined as being inverse, very inverse or extremely inverse. The typical settings for these relays are 0.7-2In (normal or rated generator current) in 1-10 second. Inducing a calibrated test current through the normal load current tests this relay.

Voltage dividers are used in a linear circuit to separate the input voltage into a small portion known as the output voltage. It is commonly used to get a low voltage signal equal to the voltage being measured.

Of or pertaining to an electron or electrons.

Thermal runaway is where the biasing and operating point is such that the temperature causes the gain to increase, which causes the temperature to increase, which causes the gain to increase, in a vicious circle, leading to destruction of the BJT. Proper biasing and gain management can prevent this from occurring.

Keyboard.

Bipolar junction transistors has two junctions base emitter junction, base collector junction. Accordingly there are four different regions of operation in which either of the two junctions are forward biased reverse biased or both. But the BJT can be effectively operated in there different modes according to the external bias voltage applied at each junction. i.e. Transistor in active region, saturation and cutoff. The other region of operation of BJT is called as inverse active region.