How Does Electricity Produce Heat and Light?

A good conductor such as copper has only very low electrical resistance. It does not get very hot when electricity flows through it, making copper suitable for household wiring.

Other metals such as iron and nickel have much greater resistance to the passage of electricity, so they become hot. A very thin wire has more resistance than a thik one, and a long wire has more resistance than a short wire. In an electric fire, coils of thin, high-resistance wire glow and produce heat when an electrical current passes through them.

In a light bulb, coils of an extremely thin conductor ensures that heat cannot be radiated away quickly enough and some of the energy is converted to light.

Electrical currents normally flow in one direction through an electrical conductor, This kind of electricity, which is produced by batteries for example, is called direct current. When the electrical current is made to reverse its direction rapidly, it is known as alternating current. This kind of electrical current is used in domestic wiring, and it usually switches direction and and back again about 50 t 60 times per second. This is the cause of the hum that you can sometimes hear near electrical equipment such as fluorescent lights.

How Does the Body Keep At Proper Temperature

The body has several systems to keep itself at the right temperature. Heat is produced by the breakdown of food substances stored in the body. The chemical reactions in the body will only take place properly if the body is kept at the ideal temperature, so any extra heat has to be removed. Heat leaves the body through the lungs, as you breathe out warmed air, and also through the skin. If you are very hot, the blood vessels near the skin’s surface open wider to increase the blood flow, so you look a bit pink. The extra blood means more heat leaves the skin surface, cooling your body.

Vigorous exercise means the body needs to generate extra energy. Some of this is produced as heat. Excess heat is removed by sweating. Sweating removes excess salt and wastes through the skin. It also helps to keep you cool because sweat takes heat away from the body as it evaporates on the skin. If you have been exercising and are very sweaty, and then stand in a draft, you will notice this cooling effect very quickly. Sweat is a watery liquid, but other skin glands release an oily substance called sebum that helps to lubricate the skin and keep it supple.

How Do Batteries Work?

Batteries produce electricity by means of chemical action. A battery contains two different conductors, or electrodes. Usually, one of these is the metal case of the battery. The electrodes are separated by a conducting liquid or paste, called electrolyte. The substances in the battery react chemically with each other to produce an electrical current. As a result of chemical activity, a positive charge builds up at one electrode, and this can flow through a conductor such as a wire to the other (negative) electrode. Eventually the chemical energy runs out and the battery becomes exhausted.

How Big Are Stars?

Our Sun is quite a small star, even though it measures 864,761 miles across, which is 109 times more than the Earth’s diameter. If the sun were the size of a football, the Earth would be less than one tenth of one inch across. Some start are known as supergiants. The star Antares, for example, is 700 times bigger than the sun. There is a start in the constellation of Auriga that may be 1,863 million miles in diameter, or 4,000 times bigger than our sun. The neutron star that remains after the explosion of a supernova may be only 12 miles in diameter, but of enormous mass. If it weighs more than two or three times that of our sun, it begins to collapse into a black hole.

Our Sun is part of the Milky Way, a huge disc-shaped collection of billions of start and interstellar derbis. Most of these start cannot be seen with the naked eye, but their combined light produces a huge milky-looking path across the night sky.

Quick Fixes For Everday Disasters

INVADING ARMY: Ants are having a feeding frenzy in your kitchen, and you don’t want to use a toxic brew to defeat them.

THE QUICK FIX: “A 50/50 mix of peppermint oil and water will get rid of ants,” says Amy Devers, co-host of the DIY Network’s “DIY To The Rescue” show. “Fill a spray bottle, and spray wherever you see them coming out of hiding.”

SPEAR FACTOR: A weed-ridden asparagus patch has you about ready to give up on your favorite crop.

THE QUICK FIX: Add salt. “Asparagus is the only vegetable that can withstand salt,” says Penny Griggs, an organic farmer in Vermont. “Spreading salt around your plants will kill the weeds but leave your asparagus unharmed.”

SPILLED JUICE: The battery in your laptop is losing its charge much faster than expected.

THE QUICK FIX: Wireless operations are a little-known drain on laptop batteries. “If you can disable your wireless networking and still get your work done, do it,” says Andy Hooper, owner of Intelligent Systems, an IT security company. “Some wireless cards can eat up half of your laptop’s power.”

FROZEN OUT: Cold weather has stiffened the mechanism of your garage door opener, causing it to lose power.

THE QUICK FIX: Most garage door openers made in the past 15 years have pressure adjustments for both raising and lowering. Check and adjust these settings seasonally to keep things running smoothly.

SCREW LOOSE: You’re trying to replace a woodscrew, but the hole is stripped and the screw won’t grab.

THE QUICK FIX: Insert two short lengths of thin, insulated wire in the hole before adding the screw. They’ll allow the screw to bite.

TRAPPED BELOW: The water in the trap of your basement floor drain dried up-and now your cellar smells vaguely of nasty, nasty things.

THE QUICK FIX: Pour nontoxic plumbing antifreeze down the drain to fill the trap. You can use water in a pinch, but it evaporates faster than antifreeze, so you’ll need to repeat the process more often.

HOT WHEELS: The temperature gauge on your car is headed for the danger zone, but you’ve got no time (or place) to park and cool your jets.

THE QUICK FIX: Turn the heater on ful blast (opening the windows so you don’t fry). The extra volume of the heater core and its hoses, as well as the airflow of the heater fan blowing across the core, may dissipate enough heat to get you home–or to the garage–without a meltdown.

ICE RAGE: Your car doors freeze shut in cold weather.

THE QUICK FIX: “Spray the weatherstripping around the door frames with silicone,” advises Al Toutant, a technician at Heath Auto Service in Greenwood, Maine, where they know a thing or two about cold weather. “It keeps moisture from collecting and freezing your doors shut in the winter, and it keeps it from drying out and cracking in the summer.”

POWER INTERRUPTION: You need to remove your car’s battery, but don’t want to lose the settings on the car’s radio, alarm, GPS and computer.

THE QUICK FIX: A 9-volt battery adapter can plug into your cigarette lighter to keep those chips powered up. Result: No more auto amnesia.

DAMPNESS AT NOON: Your clothes dryer seems to have lost its zip.

THE QUICK FIX: Clear the vent duct by removing the vent pipe and pulling out any accumulated debris from the pipe and duct. It’s a 3-minute fix that can save you a $75 visit from a technician.

How to Use Windows Movie Maker

How to Use Windows Movie Maker

Quick Fixing Tips and Tricks

UNPLANNED POOL: A big rain has flooded your basement. And, since it knocked out the power too, your usually reliable sump pump won’t pump.

THE QUICK FIX: If you live on a slope, try making a siphon. First, fill a garden hose with water from the outside spigot. Seal one end with your thumb and have a friend seal the other. Place one end through the cellar window and into the standing water. Then, have your friend carry the other end as far downhill as possible (the outlet has to be below the intake). Release your thumbs and let gravity do the rest.

SHAGGY LAWN: You need to cut the grass before the in-laws show up but your mower won’t start.

THE QUICK FIX: Before you give up and take it to the repair shop, try this. First, take out the spark plug and empty the gas. Then, get a new plug, add some fresh gas to the tank and, more often than not, the mower will start right up.

CRACKED TEETH: Someone–not you, surely–has broken a key off in a door lock, which is now jammed shut.

THE QUICK FIX: Use a grinding wheel to shape an old hacksaw blade into a harpoon-like point. Then, slip the point into the lock over one of the key nubs and use the hook to fish it out.

BLURRED VISION: The zoom shots from your fancy new digital camera are fuzzy.

THE QUICK FIX: Only use your optical zoom. Most digital cameras have both optical zoom, in which the lens moves (just like a zoom on a film camera), and digital zoom, which manipulates the image electronically. The digital zoom can compromise the quality of the image. If you want more magnification than the optical zoom can handle, it’s better to achieve it on a computer after the fact.

RISING WATERS: The toilet is about to overflow, and you know that your usual tactic of slamming the lid and crossing your fingers won’t work.

THE QUICK FIX: As soon as the water level in the bowl starts rising, reach into the tank and prop up the fill valve (the ball or cylinder that floats on top of the water). That will stop the flow to the toilet, thwarting an overflow. The plunger, however, still awaits.

IMMOVABLE OBJECT: A stubborn nut on an old lawnmower or pickup truck refuses to budge.

THE QUICK FIX: The standard tactic since the dawn of the acetylene torch has been to heat the nut until it glows red. When heat alone won’t cut it, touch a candle to the glowing nut. The wax will melt and flow into the threads, acting as a lubricant.


SNEAK LEAK: You can’t find the source of oil leaking from your engine.

THE QUICK FIX: First, spray the area with Easy Off kitchen cleaner. (It’s cheaper than automotive cleaners.) Then, hose the area down, let it dry and spray on aerosol foot powder. The oil will stain a path in the powder, which you can follow back to its source.

SUN-DRIED TOMATOES: You need a way to water sensitive tomato plants during your summer vacation, without asking your neighbor to take care of them (again).

THE QUICK FIX: Collect some liter-size plastic soda bottles and punch a few small holes in each one. Then, bury a bottle up to its neck next to each of the plants. Before you leave, simply fill the bottles; they’ll slowly release the water over the next four or five days and keep your plants from wilting.

STRUCTURAL COLLAPSE: A broken tent pole is threatening to ruin your annual family camping trip.

THE QUICK FIX: “As long as you don’t need it to hold up to serious weather, you can splint a tent pole with a branch,” says Michael Hodgson, author of Camping For Dummies. (Use medical tape, dental floss–or, yes, duct tape.) “Heck, you can even pitch a tent entirely with branches if you need to.”

POLTERGEIST DOOR: Every house has one, a door that slowly drifts shut every time you try to leave it open.

THE QUICK FIX: Rather than resetting the hinges or propping it open with a potted plant, remove one of the hinge pins, lay it over a nail atop a hard surface, and strike it lightly with a hammer until the hinge pin has a slight bend. Tap the pin back in place. The increased friction will keep the door where you want it.

How to Grow Bonsai Trees : Easy and Free Lessons…

Check out this cool video to learn how you can grow your own bonsai.

CANON DIGITAL CAMERA: EXPRESS, SHOOT AND SHARE

Canon is well known across the country as an imaging equipment and information systems. Their many products include copiers, printers, lenses, camcorders, semiconductors among others, and of course Canon digital cameras.

The latest high end canon digital camera is the PowerShot S2 IS. This is a 5.0 mega pixel Canon digital camera that features a 12x optical zoom and a 4x digital zoom. This baby is furnished with Optical Image Stabilizer (that is what the IS in S2 IS stands for) that eliminates camera shakes for people who have shaky hands or for taking camera shots. The UD lens found in this canon digital camera provide amazing color accuracy throughout the whole zoom area.

As with many digital cameras nowadays, this certain canon digital camera can record moving pictures. Now with another first, the S2 allows you to record moving pictures, and there no use for missing a perfect image incorporated with that moving picture. With the Movie Snap feature, just snap away when you see that perfect image, and it will be saved in your canon digital camera along with the recorded video.

This canon digital camera is also equipped with the DIGIC II Image processor that is designed to increase processing speed and image quality. It instantly says that with the DIGIC II, your canon digital camera has faster start-up time, playback and auto focus while giving your images the absolute brilliance.

The S2 also support USB 2.0 Hi-speed standard, so you will always have the easiest time transferring your files to and from your computer. With the USB 2.0, you can take advantage of your super hi-speed SD card.

This canon digital camera is also supplied with a 1.8 inch LCD power saving and fold out screen that?s 115,000 pixel resolution. S2 shoots at 30 frames per second; this shooting rate can be reduced when taking pictures in night display, to give you the brightness that you need when taking pictures.

On the other hand, the latest point and shoot canon digital camera is the PowerShot SD500 and the PowerShot SD400.

The SD500 is the first 7.1 mega pixel canon digital camera that gives amazing images and absolutely to die for details. It has a 3x optical zoom that enables close up shooting with a 37-111mm equivalent with a 35mm film camera. This is one of the new perpetual curve design for a canon digital camera that fits the hands perfectly.

Sporting a very slim design, you would marvel at its 2.0 inch LCD that gives easier frame and play back use.

This baby is also equipped with the same DIGIC II Image Processor found in canon digital cameras that gives you amazing features. Also USB 2.0 compatible and works with the same high-speed SD card.

Even better than most digital cameras out there, this gadget can shoot moving images to up to 60 frames per second- perfect for moving objects (especially in sports) and a 30 frames per second for shooting still images. Furnished with scene modes like portrait (blurs the background and focuses on your subject), foliage (perfect for foliage, greenery or blossoms), beach (sunny shots without the dark faces), underwater (reduced background scatter. Tip: you can always buy waterproof case for shooting underwater images), fireworks, night snapshot, kids and pets, indoor, snow and digital macro (larger than life images).

This canon digital camera even enables you to customize and correct as you shoot. With modes like lightening skin tones, positive film, darker skin tones and others, you can never go wrong with using a canon digital camera.

These are just some of the many features of the SD500. There are more to the SD500 that has yet to be discussed. Check canon?s website at www.usa.canon.com <http://www.usa.canon.com> for a full profile of the SD500 and to other latest releases and products.

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The Difference Between DVD-R, DVD+R, DVD+RW and DVD-RW Explained

There’s DVD+R, DVD+RW, DVD-R, DVD-RW, and even DVD-ROM! So what’s the difference between all of these different names, aren’t all DVDs the same? Well, it’s not quite that simple.

Let’s first start with the most obvious difference: some have R and some have RW. The “R” stands for readable, while the “W” stands for writeable.

The main difference between DVD-R and DVD-RW, or DVD+R and DVD+RW is that the R disc formats can only be written to once, and then it is only readable and can?t be erased for the rest of its digital life. While RW discs are can be written to and erased many times, they are both readable and writeable.

“R” discs are perfect if they are only needed to be written to once, such as giving some files to a friend or transferring them between PCs. “RW” discs have their strength in the ability to be used many times over, which is great for routine system backups, etc. And naturally, the RW discs are slightly more expensive than the R discs, but you’ll have to decide if the trade offs are worth the money.

Now, onto the difference between DVD-R and DVD+R. As I just described above, DVD-R & DVD-RW are sister discs, the difference being one is writeable once, while the other is writeable multiple times. The same thing is true for DVD+R & DVD+RW. So the question is, what’s the difference between the plus and minus?

In order to explain this we must take a trip back in time. When DVDs were first being developed, there was no industry standard. Multiple companies were competing to develop what they hoped would be the dominant form of the future.

The DVD-R DVD+R difference can easily be summarized by the following:

* The DVD-R/RW standard was developed by Pioneer, and is used primarily by Apple and Pioneer. These “minus” discs can only be written to in one layer on the discs surface. In addition, this format is supported by the DVD forum, but is in no way an industry standard. DVD-R/RW discs are cheaper than the “plus” format.
* The DVD+R/RW format is supported by Philips, Dell, Sony, HP, and Mcft. These discs can be written to in multiple layers, giving them slightly better and more disc storage than the “minus” format. Because of this additional capacity, they are slightly more expensive than “minus” discs.

A couple final things to clear up is the difference between DVD-ROM and DVD+RW, or the other DVD formats I mentioned above. The DVD-ROM drive can only read DVDs, while the other DVD drives can read and write data to DVDs.

And naturally the DVD+RW CD+RW difference can be explained by the “DVD” or “CD” prefix. DVDs, on average, can store up to 4.7 GB of data, while a CD can only store about 700 MB of data, or about 15% of a DVD’s capacity. While CDs are slightly cheaper, in my opinion, the benefits of DVDs are much greater.

So now that you’ve learned about the difference between DVD-R, DVD+R, DVD-RW, DVD+RW, and even DVD-ROM, which one is right for you? The easiest way to determine which is more beneficial is to watch the industry trends. A few years ago all pre-built computers were shipping with DVD-ROM drives. Today, most PCs have a burnable DVD drive.

I feel that the benefits of having a burnable DVD drive far outweigh any additional costs. They store much more data, and they are ideal for storing your home movies to watch on your DVD player.

My advice is to look at DVD burners that support all of the major formats I’ve mentioned above, DVD-R, DVD+R, DVD-RW, and DVD+RW. While a DVD drive that supports all of these formats may be slightly more expensive, it will allow you to use any type of DVD disc to burn to, and you’ll be protected from any industry shifts to one format or the other.

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