WHAT IS ELECTRICITY?
An electrical current consists of moving
“electrons.” Electrons are tiny particl
es that
you can visualize as a crowd of tiny pe
ople
rushing through a tunnel. When they r
each a
narrow spot in the tunnel, a jam oc
curs as
they all jostle together. The same thing
happens with the electrons in an el
ectrical
wire. In this case, the wire gets real
ly warm at
the narrow spot and may even start t
o glow.
That’s how light bulbs work.
ELECTRICAL CIRCUIT
An electrical circuit consists of a power source (battery), a conductor (wire), and a devic
e that uses the
electricity (motor). For the electric current to be able to flow, the circuit must be compl
ete. Another
thing that affects the flow of electrical current is how easy it is for the particles to tr
avel through the
“tunnel” — in other words, it depends on how conductive the tunnel is. Some materials s
uch as metals
(copper and silver, for example) are very conductive, so we call them conductors. Other mat
erials such
as wood, rubber (elastic), and glass are non-conductors, or “insulators”.
Tip!
Don’t forget to switch off the battery
compartment when you’re not using the
propeller. To do this, just move the
switch to the “OFF” position or remove
the wires from the springs.
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WHAT IS VOLTAGE?
We measure the tension of an el
ectrical
current in volts. To continue the
metaphor, higher voltage corresponds
to stronger tiny people. They can push
the others more strongly through the
tunnel (the “conductor”). If the voltage
is too high, the electrons have too much
freedom to move around, and can even
fly through the air. That’s when you s
ee
sparks fly.
?
WHAT’S
HAPPENING
You have just created an electrical circuit.
Electricity flows from the battery through
the wires that you connected to the
springs, into the motor, and then back to
the battery again. The motor axle
rotates, which causes the propeller to
rotate on its own axle. Can you feel the
flow of air generated by the propeller?
