Monday, June 11, 2007

Air Purifier of Electronic

Although there are various versions of air-purifiers available today in the market including the HEPA purifier and the UV air-purifier, but there are only two basic kinds of electronic air-purifiers. These are the negative ion generators and the ozone air-purifiers. We will discuss the functioning and effectiveness of both the varieties in the following section.

Recently, air purifiers are coming with indicator lights that will notify the user that it is time to change the filter inside. Previously one always had to keep an eye for that, and the replacement was based much on guess work. The average domestic owner doesn't have the expertise to understand if it is time to replace the filter. With indicator lights, that shouldn't be a problem anymore.

Ionic Air Purifiers

The basic principle of these airpurifiers is based on the concept of static electricity. What it does is while the air passes through the purifier it charges the air negatively by releasing negative ions. Now these negative ions come in contact with the positive ions present in the air. These would include the regular pollutants like dust, bacteria, pollen and chemicals. These remain suspended in the air and we breathe them in along with the air. Now the negative and positive charges immediately bond together and fall to the ground. This is a very simple and basic method, but at the end of the day it works.

In the more advanced ionic air purifiers there are plates inside the purifier which are negatively charged. When air passes through the purifier, the positively charged particulates are attracted by the plates and are collected. So the floor remains free of the pollutants.

Ozone Air-Purifiers

The second variety of electronic airpurifier is the ozone air-purifier. However, this variety of air purifier has been embroiled in much controversy and there is little indication that the controversy is going to die down anytime soon.

Ozone air purifiers actually release ozone in the air. The principle is that ozone is composed of three atoms of oxygen of which the third atom is a free radical and readily reacts with any organic substance. The manufacturers' theory is that the free radical reacts with the organic substances in the air, thus decreasing pollution. And in the process the two other atoms are now released as oxygen which further cleanses the air.

The problem is that this free radical can actually react with the organic substances inside our body and this can be very harmful for our health and can seriously damage our lungs. So according to some, ozone air purifiers do us more harm than they aid us. There is definitely a need to look into the matter more seriously and there should be more research conducted before we can come to a conclusion about this variety of air-purifier.

Friday, June 8, 2007

What is Electronic : Lesson to beginner.

The holiday season is upon us, which can only mean one thing: electronics are at the top of everyone's wish list. Even if you can't snag a new PlayStation 3 or Nintendo Wii, there are still many electronics gifts that will delight your recipients. Here are just a few:

Cell Phones: Cell phone technology continues to improve, as do the features available on cell phones. A new cell phone, complete with a high-res camera, video functionality, and wireless adaptability, is certain to be a welcome gift. If that's beyond your budget, opt for any of the number of cool cell phone accessories that are available.

iPods: An Apple iPod makes the perfect gift for anyone who enjoys music or television, even if they're not tech-savvy. Not only can they download tunes, but increasingly, they can download television episodes that they may have missed. Again, if you can't afford an iPod, there are any number of accessories - from earbuds to "socks" that are adorable and affordable.

Home Theaters: This year, why not indulge the whole family with a home theater? Flat screen TVs have come so far down in price that they're more than worth the splurge. While you're at it, get a collection of DVDs that every family member can enjoy!

Car Audio and Video: Entertainment has most definitely moved out of the home and into transportation. High-quality car audio and video equipment make wonderful gifts for family members on the go. Everyone can enjoy the high-quality sound that great car audio produces, while the kids in the family will be entertained on road trips with car DVD players.

Computers: For many people, computers aren't a convenience - they're a necessity. Everyone from adults who bring work home with them to students who have to research school papers (and book some time on one or more of the social networking sites!) will treasure a new computer. Again, prices on electronics have come down so much that either a notebook computer or a desktop PC is affordable.

Games: If you're not able to nab one of the new gaming systems, don't worry about it. There are still great games that are made for the Sony PlayStation 2, the Nintendo GameCube, and the Microsoft Xbox and Xbox 360. Final Fantasy XII, Guitar Hero II, Okami, LEGO Star Wars II, Madden NFL 07, and Viva Pinata, are all highly rated games for a variety of interests and age levels.

The bottom line is that, whatever the gift-giving occasion, you can't go wrong with a gift of personal electronics. Your best bet is to find an online source that has deeply discounted electronics, continually adds new items to their inventory, and provides you with the perfect online shopping experience.

Monday, June 4, 2007

Resistance and Resistor

In Wikipedia, resistance is a measure of the degree to which an object opposes an electric current through it. The SI unit of electrical resistance is the ohm. Its reciprocal quantity is electrical conductance measured in siemens. Electrical resistance shares some conceptual parallels with the mechanical notion of friction.

The resistance of an object determines the amount of current through the object for a given voltage across the object.

I = \frac{V}{R}

where

R is the resistance of the object, usually measured in ohms, equivalent to J·s/C2
V is the voltage across the object, usually measured in volts
I is the current through the object, usually measured in amperes

For a wide variety of materials and conditions, the electrical resistance does not depend on the amount of current through or the amount of voltage across the object, meaning that the resistance R is constant.

In electronic, a object which gave resistance is call resistor. Resistor had 2 terminal and color code at their body. Color at the resistor's body (look picture above) had value. The value mean amount of resistance at resistor.