Is electricity created at power plants?
No. Technically speaking, electricity can’t ever be “created.” The Law of Conservation of Energy states that energy cannot be created or destroyed, but can only change its form. The total quantity of matter and energy available in the universe is a fixed amount. So, at a power plant, mechanical energy (the energy contained in the movement of giant magnets past coils of wire) changes to electrical energy (the flow of electrons).
You can take this back even further…Where does the mechanical energy come from that moves the magnets? If the power plant runs on fossil fuels, then it comes from a form of chemical energy. Where does the chemical energy in fossil fuels come from? Fossil fuels are made from prehistoric plants, and plants get their energy from the sun. So you could say that electricity generated in a fossil fuel-burning plant ultimately comes from the sun.
The mechanical energy used to move the magnets in a generating plant could also come from falling water, the ebb and flow of the tides, the wind, heat from the sun, and nuclear fission. But in all cases, the energy gets changed from one form to another. It doesn’t just appear and disappear.
Who discovered electromagnetic induction?
In 1831, Michael Faraday discovered that passing a magnet through a loop of wire created a current. Soon after, Joseph Henry discovered that the current produced around any closed loop of wire is proportional to the rate at which the magnet moves through the loop. The faster the magnet moves, the stronger the current. The wire loop actually transfers kinetic energy (the movement of the magnet) into electrical energy.
What are semiconductors and superconductors?
A semiconductor is a normally insulating material that has been mixed with a few conductive atoms that cause the material to control an electric current passed through it. A superconductor is an element, inter-metallic alloy, or compound that will conduct electricity without resistance below a certain temperature.