Elenco Snaptricity® - Manual (Page 15)

Project #5
Find some clothes that cling
together in the dryer, and try to
uncling them.
Educational Corner:
Did you ever wonder why clothes cling together when
they come out of the dryer? Did you ever hear a
crackling sound when you take off a sweater? (If the
room is dark you might even see sparks.) Did you ever
feel a “zap” when you touch someone wearing a
sweater on a dry day? These effects are caused by
electricity. We call this
static electricity because the
electrical charges are not moving, although pulling
clothes apart sounds like static on a radio. When
electricity is moving (usually through wires) to do
something in another place, we call it an
electric
current .
Electricity is an attraction and repulsion of particles in
a material. All materials are made up of atoms , which
are really, really tiny. Atoms have a nucleus (which has
positive electrical charges), which is surrounded by tiny
electrons (negative electrical charges). When you rub
a material, electrons can move on or off the atoms,
giving them an electrical charge.
Electricity exists everywhere, but is so well balanced,
that you seldom notice it. But, sometimes differences
in electrical charges build up between materials, and
sparks can fly. Lightning is the same effect as the
sparks between clothes, but on a much greater scale.
A cloud holds static electricity just like a sweater.
Photo courtesy of: NOAA Photo Library, NOAA Central Library;
OAR/ERL/National Severe Storms Laboratory (NSSL) [via pingnews].
Why do
you often “see”
lightning before
you “hear” it? It is
because light
travels faster than
sound.
Note: This project works best on a
cold dry day. If the weather is
humid, the water vapor in the air
allows the static electric charge to
dissipate, and this project may not
work.
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Electrons
–
–
–
–
–
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Nucleus
This diagram shows the
structure of an atom, except
that the nucleus and
electrons are actually much
farther apart.
The crackling noise you hear when
taking off a sweater is static
electricity. You may see sparks
when taking one off in a dark room.
Electricity You Can Wear
Snappy says: clothes
can cling together
because electricity is
all around us.
Rub a sweater (wool is best) and
see how it clings to other clothes.