-
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.
Use these links to visit another section of
the site.
|
