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NEW! Are electricity and fossils REALLY important?
—Ritvik

Answer: I'm going to assume you mean "fossil fuels" when you say fossils. Yes, electricity and fossil fuels ARE really important! Natural gas is a fossil fuel. Try to imagine life without all the things you use that are powered by electricity and natural gas. Natural gas is used for cooking and heating, as well as to generate the electricity that powers your technology items, your entertainment, and essentials like lights. Our world would be very different without the things that electricity and fossil fuels make possible.

Why are fossils important?
—Sue

Answer: Millions of years ago, even before the dinosaurs, tiny plants and animals died and settled to the bottoms of lakes and oceans. Eventually these fossilized remains were covered by sand and mud. They then decomposed and as a result of the earth's heat and pressure, the fossils were converted to natural gas.

How is an electric current formed in the earth's core?
—Peter

Answer: Scientists do not know for sure how an electric current is generated inside the earth because it is so hard to test, but here is one popular hypothesis. Inside the earth's outer core is molten metal that heats to very high temperatures and causes the particles in it to become charged (ionized). These charged particles are subject to circulating waves of heating and cooling as the high temperatures in the core fluctuate. The movement or flow of the charged particles causes the electrical current, which in turn creates the earth's magnetic field.

Why are there shoes and balls on power lines?
—Kate

Answer: Shoes are on power lines because people toss them up there. There are numerous reasons why they do this, but none of them have to do with electricity transmission or safety! Hanging shoes are a potential hazard to the line, so don’t ever do this yourself. The balls you are referring to are warning indicators for low-flying aircraft. These colored balls alert pilots to the presence of the lines so they don’t fly into them. We may be able to see power lines clearly from the ground, but from the air they are hard to detect. In areas of bird migration they protect birds from hitting the lines as well.

Is static related to electricity?
—Laura

Answer: I am assuming your question is related to static electricity. (If you were asking about static on phone lines, please submit this as another question and I will respond accordingly.) When an object builds up an electric charge it is called static electricity. Static electricity is created by an imbalance of positive and negative charges. This occurs when the outer electrons from one substance get free from their atoms and attach to another substance, thus giving the second substance a negative charge. Electrons can get free when two items rub together creating friction—like your shoes shuffling across a rug. Two things with opposite charges will pull toward each other, creating a flow or current.

So yes, static is related to electricity, but static electricity is different from electrical current because it does not flow continuously. For more information about this, go to the Energy Science-SMART/Fire in the Sky/Science Concepts section of this website.

Why don't birds get killed when they are on a power line?
—Laura

Answer: Birds can sit on power lines and not get electric shocks because the electricity is always looking for a way to get to the ground. The birds are not touching the ground or anything in contact with the ground, so the electricity will stay in the power line. But if a bird with large wings touches a power line and a tree or power pole at the same time, it gives electricity a path to the ground, and could be shocked. And if a bird touches two wires at once, it will create a circuit—electricity will flow through the bird and likely electrocute it.

Why is electricity dangerous to touch?
—Laura

Answer: Electricity is always looking for the easiest path to the ground. So if you contact electricity from a power line, or even from an electrical appliance like a toaster or hair dryer, electricity will use YOU as its path to the ground and you will be shocked or electrocuted. Electric shock can cause muscle spasms, a rapid pulse, severe burns, weakness, shallow breathing, unconsciousness, or even death. Learn how to prevent this by visiting the rest of this website.

Why is electricity so important?
—Stephanie

Answer: If you think about it, you'll realize that our modern lives would practically come to a standstill without electricity. For starters, we use it to bring light to our homes, schools, and workplaces; to heat and cool our buildings; to power our manufacturing equipment, appliances, and other electrical devices like music players and TVs; and to communicate through phones and computers. Things would be pretty dark and quiet without electricity!

When you touch a light bulb, it's hot, but what happens to the electricity from the bulb?
—Kate

Answer: A regular incandescent light bulb is hot to the touch because over 90% of the electricity that flows into it is lost as heat. The rest of the electrical energy is converted to light when it heats up a wire inside the light bulb called a filament. The filament is made of tungsten, a metal that stays solid at very high temperatures. When the tungsten heats up, it glows and emits light through the bulb. By contrast, compact fluorescent bulbs (CFLs) are energy efficient because they waste very little electricity as heat, and thus most of the electricity passing into them goes to producing light. This is even more the case with the newer, most efficient, light-emitting diode (LED) bulbs, like those used for holiday lighting.

Why is natural gas called “natural” gas?
—Ryan

Answer: Natural gas is called “natural” because when this type of gas was first discovered, it could be used directly from the ground in its natural state, without any processing. Today, gas utilities process natural gas by removing water, sand, and other compounds so that when the gas is delivered to your home it will burn as cleanly and efficiently as possible.

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