From running a home computer to lighting
up the world’s cities at night, electricity
powers almost everything that we use.
Electricity is one of the most useful forms
of energy because it can be readily converted
into other types of energy such as light,
heat, or movement. Electricity results
from the behaviour of tiny particles,
called electrons, each of which possesses
an electric charge. When an electric charge
builds up in one place it is called static
electricity. If the charge flows from place
to place it is known as current electricity.ELECTRICITY
110
- All conductors have a certain
resistance to the flow of an electric
current. When a conductor resists
the current, the electrical energy
is turned into heat. - In power stations, the force
to rotate the coils is provided by
water power (hydroelectricity), or
by steam heated by oil, coal, gas,
or the process of nuclear fission. - A current only flows if it has a
circuit to travel around. A current
needs a conductor to flow through,
something to power, and, usually, an
energy source to drive the current. - A flash of lightning is a giant
spark of electricity driven by static
electricity (charge) that builds up
inside a cloud from a collision of
ice crystals and water droplets. - Static electricity also occurs when
you comb your hair or take off a
synthetic sweater. It is caused by
two things rubbing together and
creating a charge. - Electricity is generated when
coils of wire are rotated in
a magnetic field. This forces
electrons along the wire to
form an electric current. - The human body is full of
electricity. The 100 billion nerve
cells in each person’s brain work
by sending messages in bursts
of electricity (impulses).
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