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NEW! What is an atom?

Answer: An atom is the smallest unit of matter. It consists primarily of empty space, along with a positively charged nucleus at the center, surrounded by a cloud of negatively charged electrons. Because of magnetic attraction, the “positive” protons inside an atom’s nucleus attract the “negative” electrons outside of it. Under normal circumstances, an atom has an equal number of protons and electrons, and is said to be “electrically neutral.”

Since we are seeking to learn about electricity on this website, I will make the connection for you that electricity is a form of energy carried by the movement of electrons. This occurs when an outside force—like light, heat, pressure, or a chemical reaction—serves to break electrons free so that they can flow between atoms. The continuous flow of electrons from atom to atom through a conductor is called electric current.

 How high of a voltage can electricity go to?

Answer: In theory, there is no limit to the highest possible voltage that could exist, but the voltages we can create are limited by our technology. Typical high-voltage power lines can carry up to 765,000 volts, and the world’s highest-voltage line in China carries 1.1 million volts. The highest man-made voltage was at a laboratory in Tennessee, where scientists once managed to generate 32 million volts. Even greater voltages can occur in nature -- the highest-voltage bolt of lightning ever recorded was 1.3 billion volts!

What is an ohm?

Answer: An ohm is a unit of measurement used to describe resistance to the flow of electricity. The higher the ohms, the greater the resistance. For example, dry, unbroken skin has resistance of 50,000 ohms while wet skin has resistance of only 300 to 500 ohms. (This is why you can be shocked more easily by electricity when your skin is wet or you are standing in water.) The concept of the ohm was first developed by the 19th century German physicist and mathematician Georg Simon Ohm.

How does lightning work?

Answer: Lightning starts in thunderclouds, when small bits of ice (frozen raindrops) collide as they circulate. These collisions create electrical charges that fill up the cloud, with positive charges forming at the top of the cloud, and negative charges forming at the bottom. Because opposites attract, the concentration of negative charges at the bottom of a cloud causes a positive charge to build up on the earth beneath it. The electrical charge from the ground occurs around anything that stands out, such as trees, mountains, flag poles, or people. The charge reaching down from the clouds eventually contacts the charge rising from the earth, and ZAP!—lightning strikes!

What are the most common types of energy?

Answer: By “types” of energy I think you mean the forms of energy that people buy and use in their lives. The most common types of energy that people use in their homes in the U.S. are electricity and natural gas. Less common forms used are propane, wood, and heating oil, as well as various forms of renewable energy such as solar, wind, and biomass. For transportation, most people use gasoline, but diesel fuel, electricity, and vegetable oil also are used for transportation. And then there’s good old people power—using our legs for walking or biking!

I’m a 5th grader and I’m currently part of a FIRST LEGO League competition. This year’s theme is TRASH TREK, and our team’s idea was to get rid of trash by burning it to produce energy, which is done in many European countries and some places in the USA. I was wondering if We Energies has worked on a similar idea for the state of WI. Based on our calculation using data from trash to energy, we can produce enough energy to power all the homes in WI. If We Energies worked on such an idea, we were wondering about how much the cost would be and what would be the pros, and cons? If I can get the contact of your subject matter expert, that would be very helpful to present our project in a more meaningful way.

Answer: Thank you very much for your question and your interest in alternative energy supplies. You are correct that, in many parts of the world, trash is burned for energy. This has the benefit of reducing landfill space and generating energy at the same time. However, as with many things, it is not that simple.

In order to properly burn trash to produce energy, it must be done in a plant that is designed for that purpose. There are some important items that must be taken into account when you build such a facility. First, the U.S. Environmental Protection Agency has specific regulations for burning trash. These regulations require very costly pollution control equipment for all of the various pollutants that are created when trash is burned. Also, it is very difficult to predict or control what comes in the trash. While you have no control over the types of things people put in their trash, the plant would still be responsible for the emissions that come from it. Finally, with our advances in recycling (particularly of paper products and plastics) the energy content of trash is much lower than it used to be, making it harder to justify the cost of building this type of plant.

In general, the cost to build a trash-burning facility that could generate 50 megawatts of electricity would be on the order of $250,000,000.

How do people do work with power lines?

Answer: People who work with power lines are known as line mechanics or troubleshooters. I am guessing you are wondering how these workers repair power lines without getting electrocuted. Sometimes they turn off the electricity to the lines before working on them. If line mechanics or troubleshooters must repair live power lines, they use special protective equipment—gloves, shoes, sleeves, and other equipment—that insulate them from electricity and prevent them from getting shocked or electrocuted. Line mechanics and troubleshooters receive many years of safety training before they are allowed to work on live power lines.

What is electricity made out of?

Answer: Electricity starts with atoms, the tiny particles that make up everything around us. Even tinier particles called electrons orbit the center of atoms. When electrons move between atoms, electricity results. The electricity we use in our daily lives is typically produced at power plants, where various energy sources are used to turn turbines. The turbines turn electromagnets that are surrounded by heavy coils of copper wire. The moving magnets cause the electrons in the copper wire to move from atom to atom, generating electricity.

How do you make a battery and how does it make electricity?

Answer: A store-bought battery such as you would put in a flashlight is called a dry-cell battery. To make your own battery, however, you would make a wet-cell battery, which can be done using a lemon. Both dry-cell and wet-cell batteries create electricity through chemical reactions that occur inside them. To make a lemon battery, you would put two pieces of different types of metal, such as a penny and a nickel, in slits at each end of the lemon. If you connect a piece of copper wire to both of the coins, the circuit is closed, and a chemical reaction between the lemon acid and the metals will produce spare electrons. The electrons flowing in the circuit creates electric current.

Who made electricity?

Answer: Electricity is a form of energy that naturally occurs. It wasn’t so much “made’” as “discovered” and then put to use to serve human needs. Benjamin Franklin is the first to record his discoveries and experiments with electricity in the 18th century, and Thomas Edison invented the electric light bulb and the country’s first central electric power system in the late 19th century. You can read more about them, and other scientists who developed aspects connected to electricity, in the Tell Me More section of the Electrical Safety-SMART area of this website at


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