Creating Electricity using a Generator:
If a magnetic field can create a current then we have a means
of generating electricity. Experiments showed that a magnetic
just sitting next to a wire produced no current flow through
that wire. However, if the magnet is moving, a current is induced
in the wire. The faster the magnet moves, the greater the induced
current.
This is the principal behind simple electric generators in
which a wire loop is rotated between to stationary magnetics.
This produces a continuously varying voltage which in turn produces
an alternating current .
Diagram of a simple electric generator is shown on the left.
To generate electricty then, some (mechanical) mechanism
is used to turn a crank that rotates a loop of wire between stationary
magnets. The faster the crank turns, the more current that is
generated.
In hydroelectric, the falling water turns the turbine. The
wind can also turn the turbine. In fossil fuel plants and nuclear
plants, water is heated to steam which turns the turbine.
Reference: http://zebu.uoregon.edu/1999/ph161/l3.html
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