Static Electricity,Non-electrical energy

Static Electricity
Charge carriers, particularly electrons, can build up, or become deficient, on things
without flowing anywhere. You’ve probably experienced this when walking on a carpeted
floor during the winter, or in a place where the humidity was very low. An excess
or shortage of electrons is created on and in your body. You acquire a charge of static
electricity. It’s called “static” because it doesn’t go anywhere. You don’t feel this until you
touch some metallic object that is connected to earth ground or to some large fixture;
but then there is a discharge, accompanied by a spark that might well startle you. It is
the current, during this discharge, that causes the sensation that might make you jump.
If you were to become much more charged, your hair would stand on end, because
every hair would repel every other. Like charges are caused either by an excess or a deficiency
of electrons; they repel. The spark might jump an inch, two inches, or even six
inches. Then it would more than startle you; you could get hurt. This doesn’t happen
with ordinary carpet and shoes, fortunately. But a device called a Van de Graaff generator,
found in some high school physics labs, can cause a spark this large

Non-electrical energy

In electricity and electronics, there are many kinds of phenomena that involve
other forms of energy besides electrical energy.
Visible light is an example. A light bulb converts electricity into radiant energy that
you can see. This was one of the major motivations for people like Thomas Edison to
work with electricity. Visible light can also be converted into electric current or voltage.
A photovoltaic cell does this.
Light bulbs always give off some heat, as well as visible light. Incandescent lamps
actually give off more energy as heat than as light. And you are certainly acquainted
with electric heaters, designed for the purpose of changing electricity into heat energy.
This “heat” is actually a form of radiant energy called infrared. It is similar to visible
light, except that the waves are longer and you can’t see them.
Electricity can be converted into other radiant-energy forms, such as radio waves,
ultraviolet, and X rays. This is done by things like radio transmitters, sunlamps, and
X-ray tubes.
Fast-moving protons, neutrons, electrons, and atomic nuclei are an important form
of energy, especially in deep space where they are known as cosmic radiation. The energy
from these particles is sometimes sufficient to split atoms apart. This effect makes
it possible to build an atomic reactor whose energy can be used to generate electricity.
Unfortunately, this form of energy, called nuclear energy, creates dangerous byproducts
that are hard to dispose of.
When a conductor is moved in a magnetic field, electric current flows in that
conductor. In this way, mechanical energy is converted into electricity. This is how a
generator works. Generators can also work backwards. Then you have a motor that
changes electricity into useful mechanical energy.
A magnetic field contains energy of a unique kind. The science of magnetism is
closely related to electricity. Magnetic phenomena are of great significance in electronics.
The oldest and most universal source of magnetism is the flux field surrounding the
earth, caused by alignment of iron atoms in the core of the planet.
A changing magnetic field creates a fluctuating electric field, and a fluctuating
electric field produces a changing magnetic field. This phenomenon, called electromagnetism,
makes it possible to send radio signals over long distances. The electric
and magnetic fields keep producing one another over and over again through space.
Chemical energy is converted into electricity in all dry cells, wet cells, and batteries.
Your car battery is an excellent example. The acid reacts with the metal electrodes
to generate an electromotive force. When the two poles of the batteries are
connected, current results. The chemical reaction continues, keeping the current
going for awhile. But the battery can only store a certain amount of chemical energy.
Then it “runs out of juice,” and the supply of chemical energy must be restored by
charging. Some cells and batteries, such as lead-acid car batteries, can be recharged
by driving current through them, and others, such as most flashlight and
transistor-radio batteries, cannot