Electronics

Conventional current flow refers to a flow of positive charges. It is a kind of ficticious current. If - as is often the case - the real current is an electron flow (negative charges), then the conventional flow is a current in the opposite direction as the electron movements, since this would have the same effect (for example on the magnetic field, or on conservation of charge).

In the 1970s, "Smiley" was fairly bland: a smile or frown. Most were printed large, such as 8 and 1/2" by 11" sheets as a cheap printing to plaster on telephone poles. Of course, all were bright yellow faces with black features. Later, hair was added but never replaced the original Smiley.

This term can mean different things in different places. Some states recognize that facsimile and email transmissions can be used as "proof" of signature, and have adopted the "electronic signature" definition to refer to these sorts of transmissions and allow them (or restrict them) as evidence of (for example) intent to contract or authentication of official orders.

Other definitions mean an "electronic signature" is the electronic capturing of a physical, handwritten signature, as where you use a scribe at a point-of-sale terminal to "sign" a credit card transaction. Again, the regulations authorize this sort of paperless record as evidence of an intent to be bound by some agreement.

Without such statutes or regulations, the standards would still require a physical piece of paper (or other physical substrate) with a hand-written "signature" before a document would be admissible as proof of an original signature.

In other places, where the concern is for a more robust authentication and non-deniability, the "electronic signature" may be distinguished from a "digital signature", which uses sophisticated encryption techniques for security. There are many interesting uses for digital signatures, including anti-virus protection in critical software.

One effect of using electronic signatures (or digital signatures) is to shift the burden of proof. "You deny you signed, yet I have this electronic record showing you signed, now you have to prove this record is false."

yeast infection

A switch is a means of making (on) or breaking (off) an electrical circuit.

One advantage to using email is that it is delivered extremely fast. You can send email 24 hours a day and send communication to many people at the same time.

Every camera that records is compatible with youtube. If it is a webcam, just upload the file. If it is a camorder, use a video software to upload your video from the camorder to the computer.

There are several brands and models. Knowing the model is essential. First you have to enter the programming mode for the lock your working with. This is why we need to know. Entering the programming mode and following this with the old 6 digit code. They by entering the new 6 digit code twice, your new code is entered. It really is that easy. Most models use the pound key to enter the star key to exit the programming mode. Searching on line by the products name and model is a way to find the instructions. They are available and are easy to find. Since you have to know the old code to program, the instructions are available.

Enter this address in your web browser and it will automatically download the electronic talking battleship user manual:- http://www.hasbro.com/common/instruct/Battleship(electronic)talking.PDF

That would be a capacitor, which stores charge on it's plates when exposed to a voltage and discharges it when exposed to an input resistance. It can smooth ripples in current by it's tendancy to maintain voltage, so it can simulate the average violtage over time by discharging when the circuit voltage is low.

They are much smaller and much faster than when the first computer was invented.

Outlook! In The Old Versions Of Windows It Was Called "Outlook Express"

One can purchase an electronics kit at a number of different stores. Radio Shack always has a bunch of different electronics kits. These kits are for both kids and adults.

Yes, but not the regular store-bought batteries, the PlayStation Move controller and the Navigation Controller are powered by a built-in rechargeable Lithium-ion battery. They require batteries because they are wireless.

A Computer

Electronic highway message boards communicate road conditions, traffic conditions, and public service messages. Wait times in back-up traffic, alternate routes, and construction zones are some of the messages communicated on highway message boards.

The magnetron of the microwave is an extremely powerful transmitter of microwaves at the frequency of 2.45GHz. At this frequency fats and water absorb the energy by means of dielectric heating.

The metal inside of the microwave oven will not cause problems since it is earthed and act as a shield, it absorbs any electric field continuously over its relatively large and smooth area. Therefore no charge builds up, because it is earthed. It is so effective as a shield, that it would never leak as much as 10W/m2 at 5cm distance. Most manufacturers would specify leakage at 5mW/m2 as maximum while the magnetron inside produce about 800W of radiative power. Other experiments show that it can reduce a RF signal of 2.4GHz with about 100 times.

It is usually unearthed metal objects with sharp points thats cause arcing. The object act as an antenna and accumulates an electric charge from the electric field that is perpendicular to the magnetic field of the electromagnetic field transmitted by the magnetron. The electric charge tends to be more concentrated at sharp points without any path to discharge. Once the charge is large enough and the distance between this charge and the grounded shielding is short enough. The breakdown potential of air is bridged which acts in the same way as lightning does. Once the charge accumulate to a potential difference that exceeds 3MV per meter between the object and the earthed shielding, then the air becomes a conductor due to the great amount of electrons stored in the field around the conductive object. Then the charge on the metal object will discharge towards the shielding which is the shortest path to the ground. Once the most of the electric charge is transferred to the earth, the charge becomes significantly less and to little to continue the breakdown condition. The air becomes an insulator again and the spark is gone. This will be the case until the charge is generated again to a voltage of 3MV per meter.

This charge and discharge cycle can happen at fast intervals causing a buzzing or arcing sound. The breakdown potential is not only breaking down the air, but it also has to break down through the painted layer in the inside of the shield. It will be the same as with electronic capacitors that blow as the potential passes the breakdown potential, so would the painted layer of the inside of the microwave oven also burn and be seriously damaged. The temperature in the spark can run up to thousands of degrees centigrade.

Another problem can be electric current induced and received in thin foil that will cause heating or even fuse or melt. If a CD or DVD is placed into a microwave oven then the metal coating at the rear side of the disk will most likely melt away not because of the arcing as such, but because of high current flow through the thin metal layer which can even melt the plastic.

Not all metal objects in a microwave would actually spark. Some objects such as grills that are specially designed for microwave ovens often is designed to be large and smooth surfaces or even earthed. They would actually work in a microwave oven without problems. Whether the object will spark or not, has much to do with the shape, sharp points, clearance, earthed or not etc. Often aluminum containers may work well in a microwave as long as its sides are smooth and do not touch the sides, while a fork will spark like crazy due to the high charge that is concentrated at the tips. This however is not easy to assume for all metal objects whether it will spark or not. In some cases aluminum foil can be used in a microwave to shield of some parts of food that do not need as much heating. The normal foil is thick enough not to heat up from the current. But then again, wrinkled foil can be very unsafe because of its unevenness and its pointy texture. Therefore I would not recommend to experiment with metal objects in a microwave oven. Stick to the manufacturers specifications. It can cause serious damage to your microwave if the experiment would fail.

This is also the reason why we shouldn't use cellular phones at gas stations, although the risk is practically very small that the cell phone will cause nearby metal objects to spark and cause the fuel to ignite, it is theoretically possible in some scenarios to happen. However the microwave oven often is about 300 - 3000 times more powerful than a cell phone transmitter section and therefore the effect of a cell phone has on metal objects are significantly less.

Yes that would work. It's all about the ratio. As long as the rated voltage is not exceeded, as there will be a limit to what the insulation can stand, before breaking down. Lower voltages than rated will be safe.

In my books...Panasonic - I got one for a wedding gift in 1981. I finally replaced in in Debember 2006 when it finally broke!

The most common electronic hand tool is an electric drill, which can be used to put holes into an object (usually wood) and can also be used to drive screws into a substance, or to pull them out.

I believe that the general consensus about technology is that anything that makes life easier, that doesn't require too much effort or money, is a good thng. However, the younger crowd, like me, who are more interested in these kinds of things, like to get their hands on the brand new stuff, like the iphone and xbox 360.

* invented the two-way television telephone or videophone (1955) patented as a "photo phone signal separator network" * discovered the physical law of electrical kinetic resistance called the Zara effect (around 1930) * invented an airplane engine that ran on plain alcohol as fuel (1952) * improved methods of producing solar energy including creating new designs for a solar water heater (SolarSorber), a sun stove, and a solar battery (1960s) * invented a propeller-cutting machine (1952)