Data Sheet
Science Database
You will need:
Electrical current and
electronics
For a long time, researchers have puzzled
over the nature of “electrical current.” It is in-
visible, with only its effects being noticeable.
Today, we know that it is a “flow of electrons.”
Electrons are smaller and more mobile than at-
oms, and they have lots of unusual properties.
Normally, “electrons” are firmly attached to
the atom they belong to. But sometimes, espe-
cially in metals, electrons can get free and zoom
around among the atoms. You can picture elec-
trons in a wire like water in a pipe.
When water is set in motion by a pump, it
starts to flow through the pipe. This flow can be
used to drive a small water wheel, for example.
With electricity, too, there are things like
pumps (for example, batteries) that set the
electron cloud in the wire in motion. This is
called “electrical current.” You can use elec-
trons to do lots of amazing things. The tech-
nology of controlling electrons toward certain
goals is called “electronics.” With the help of
transistors, capacitors, resistors, and LEDs, we
can make electrons do what we want them to.
3
Green instead of red
You performed the previous experiments with the
red LED. Now it’s the green LED’s turn to shine.
• Batterybox • Selectorswitch
• 4X-connectors • GreenLED
• 1I-connector
Here’s how:
Assemble the same circuit as in Experiment 1, except
this time use the green LED. Its green light will shine
as soon as you push the switch.
How it works:
The green LED works just like the red one, except the
light-emitting material has been changed so that it
produces green light.
Electrons
Direction of flow
used to drive a small water wheel, for example.
With electricity, too,
there are things like
Pump
Water wheel
Electrical current and
Electrical current and
Electrical current and
Electrons
Atomic
nucleus
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