Ask the Superexpert about Electricity

Have you ever wondered why shoes hanging on a power line don’t get fried? Or why natural gas flames are blue? Now you can get answers to these and all your energy-related questions. Just Ask an Expert!

The Expert answers new questions regularly, so check back to see if YOUR question is up!

A most interesting question, Karen! The first answer that comes to this SuperExpert’s mind is this: “We have electricity so that I can see this question on my computer and answer you.” I’m glad Thomas Edison invented the lightbulb—and developed and built the first electricity generating plant in New York City in the late 1870s—so I have a bright, consistent and safe way to see and communicate with you and other students. Without electricity, I’d have to use the flame of candles or lamps to see, and the pony express to deliver your question to me and my answer to you, which would take weeks! Electricity makes this and many other activities much easier.
In our archive section on this site, Carlos asked a similar question to yours, but I’ll be happy to repeat some of that answer here for you as well. We need energy to function – it’s what makes anything and everything move, change, and/or grow. All living things use energy. Without energy we would be like rocks sitting stationary on the ground. Unlike rocks, we can run, jump and dance, which we can attribute to the power of energy! Click here to visit our Energy-SMART section and learn more about energy.
We define energy as the ability to change or move matter. (Matter is anything that has a size or shape and takes up space.) Energy comes in many forms, but it is not like matter, as energy has neither a size nor a shape. There are many different types of energy, including chemical, radiant, mechanical, electrical and nuclear, and none of these have a shape. Click here to visit our Energy-SMART section and learn more about energy.

Let’s start with a period at the end of a sentence on a typical printed page. There are 7.5 trillion atoms in that period, and each atom contains at least one electron. Now imagine all the electrons in all the atoms in all the periods at the end of all the sentences on all the printed pages on earth—and all the atoms in everything else on earth as well. You will find that the number of electrons in this world is too big to count—and maybe even too big to imagine!

Power lines are designed differently based on the amount of voltage, or pressure, of the electricity they carry. Thicker power lines typically carry higher-voltage electricity, and thinner power lines typically carry lower-voltage electricity. But no matter their size, all power lines are dangerous to contact—so always stay far away from them!

People may throw shoes up on a power line because they think it’s clever or fun and they may not realize the shoes create a dangerous situation. If the shoes touch two power lines at the same time, or if they touch a power line and a power pole at the same time, they could start a fire. And anyone who tries to get the shoes down could be seriously shocked or even killed. So if you ever see someone throwing shoes up onto a power line, tell them to stop! And please call Xcel Energy to report any shoes you see hanging from power lines in your neighborhood.

Some other students asked these questions a short while ago. Please see my responses to them below.

When you turn on the ignition of a car and start driving, you turn the potential energy stored as gasoline in the car into kinetic energy, the energy of motion. When you go downhill in a car, gravitational potential energy helps you along.

There is no “best” energy to use. Each type has its advantages and drawbacks. Xcel Energy relies on a mix of different types of energy sources to generate the electricity that we use in our homes. Nonrenewable energy sources such as coal, oil, and natural gas are lower in cost but will ultimately run out (that’s why they’re called nonrenewable), and may have more of an impact on the environment than renewable energy sources such as solar, wind, hydro, and geothermal energy. But renewable energy sources may be less available depending on your geographic location, and they can be more expensive.

Energy is the ability to do work of one sort or another. This could be throwing a ball, lighting up the sky like lightning does, digesting food, or creating heat in a fireplace. Each of these types of “work” constitutes one of the different types of energy, which are mechanical, electrical, radiant, chemical, thermal, and nuclear.

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