The Science of Everything: Electricity

Electricity is essential to everyday life, yet, the process of how it works still baffles most of us. Dr. Brian Campbell Deem, full-time physics lecturer at Loyola University, explains how electricity starts with atoms.

Atoms are the microscopic building blocks of our world, from the air we breathe to the cable that powers our computer. Each atom in that cable has a core that is positively charged, and revolving around it are even smaller negatively charged electrons. These electrons are loosely held in place and can be knocked off or forced away from the atom. 

“To turn on an incandescent light bulb we can use a battery that has its own positive and negative charges,” Brian explains. “The battery creates a voltage difference, the ‘push’ that makes the electrons start to move.” The negatively charged electrons in the cable are attracted to the positively charged side of the battery. All these electrons keep bumping into each other just like people in a crowded room. “Every bump creates heat, which starts to emit more visible light.” says Brian. 

While powering one lightbulb seems simple enough, providing a whole city with electricity requires heavier machinery. Power plants in a city use things like coal, oil, and nuclear energy to heat water. The resulting steam spins a turbine, which causes rotation of a generator. That rotation creates a voltage difference, the ‘push’ that causes electrons in the power lines to move and provide energy to city residents. 

But electrons don’t have to physically make the journey from the power plant all the way to your house to provide energy. The power lines in the city, cables in our wall, charging cables, and our electronic devices all have electrons that work together to accomplish this. The ‘push’ from the generator causes electrons close to the power plant to start moving. They bump into other electrons and now those start moving. This process continues all the way from the power plant to your home. When you plug your charger into a wall outlet, the electrons in your cable and device become part of that system and now they start to move, too. 

But why do outlets look different abroad? If you choose to travel away from home, you will still be able to charge all your devices, but do not forget your power adapters that convert the voltage (the ‘push’) from the wall outlet to a level that’s compatible with your devices. “Europe has a higher voltage standard (220-240 Volts compared to 110-120 Volts in the U.S.) so all of their electronics are built to withstand that,” says Brian. Don’t skimp on the power adapters because “if your material was not built to handle that, then it can melt the wires or catch fire,” warns Brian.  

Though electricity is a fascinating topic, learning it takes commitment. “I continue to struggle with a lot of physics and math,” Brian shares. “I failed an electricity and magnetism exam in my undergrad.” Committing to the learning process made it possible for him to earn a bachelor’s, master’s, and PhD in physics. Now as one of Loyola’s admired physics instructors, he passes along some encouragement: “Don’t be dissuaded from learning something because it’s difficult. Learning is a struggle and it’s not supposed to be easy,” a great thing to remember when you’re learning anything new, electricity or not.